Admissibility of Text Messages


[Editor’s Note: Alicia Penn joined the NLST in September of 2023 from the District of South Carolina Federal Defender Office, where she represented clients charged with offenses involving everything from turtles to terrorism. A career Public Defender, she was forced to become proficient in electronically stored information after being assigned a 3-terabyte lottery scam case in 2013. Ever since, she has worked to adapt to the ever-changing electronic landscape and make it work in favor of her clients. In her new role her goal is to provide practical solutions to technological problems.]

Are screenshots of text messages admissible? The answer is everyone’s favorite: it depends!

There is no federal rule expressly forbidding the use of screenshots of text messages in court, but not all relevant evidence is admissible. To get a screenshot admitted and considered by a judge or jury there are procedural hurdles to overcome. Conversely, if your goal is to keep a screenshot out, the federal rules give you a framework to argue against admission.

The Rules:

Federal Rule of Evidence 901(a): In general, the proponent of the evidence must produce evidence sufficient to support a finding that the item is what the proponent claims it is. (b) gives examples of evidence that satisfies this requirement.

Other federal rules you can make hay with are: 1002 (Best Evidence), 401 (Relevance), 801 (Hearsay).

For a thorough and beautiful rubric of how to admit or challenge admission of electronic evidence, see

Admissibility of Electronic Evidence Chart by Hon. Paul W. Grimm and Kevin F. Brady (2018) Brady Evid Admiss Chart 2018.pdf

In addition, an excellent primer on admitting evidence in federal court is Lorraine v. Markel American Insurance Co., 2017 U.S. Dist. LEXIS 33020 (D. Md. May 4, 2007).

The Argument:

With reliability as a framework, there are two ways screenshots of text messages are inherently unreliable.

  1. The text message itself is fake.

With only the screenshot, there is no way to prove a text message is real. Anyone can create an image that looks like a text message using a free online program, screenshot it, and then send it or show it to someone and claim it is real. Without any other proof, such as a direct download from a cellphone, subscriber records, IP address data, etc. there is no way to prove that the text message itself was a real message that existed in the way the government witness may claim.

I made the fake chat at the beginning of this post online, for free, entering no personal identifying information, downloading no software program, in two minutes, after Googling, “fake chat generator.”

You can imagine the ways a fake text message could be used against a client. I have had a case where the government wanted to use screenshots of text messages, supposedly received from an informant, and claimed that these screenshots proved my client planned armed robberies. When I showed the screenshots to my client, he denied ever creating or sending them. The government had no other corroborating evidence or witness to show the text messages were real or received from my client. I objected and argued the supposed screenshot was unreliable.

  1. It is a real text message, but the sender/receiver is fake.

This scenario requires only a little more effort. There are apps like TextNow that allow you to send anonymous text messages. In one of my other cases, the government shared screenshots of threatening text messages sent from an anonymous number to my client’s ex-girlfriend and claimed my client had used TextNow to send these messages. Based on these screenshots of text messages, my client was detained, even though I argued the screenshots of text messages were unreliable and shouldn’t be considered. After the hearing, my investigator subpoenaed TextNow for subscriber information linked to the numbers used at the times the texts were sent. TextNow responded within a day, and the subscriber implicated the ex-girlfriend’s new partner as the person who created the text messages and sent the threats. After explaining and presenting this new information to the government and court, my client was released on an unsecured bond.

Cases that talk about screenshots and admissibility:

So, what is enough to admit a screenshot?

In United States v. Walker, 32 F.4th 377 (4th Cir. 2022), a government agent’s personal knowledge about the original report and the comparison of that report with a screenshot of letters calling a victim a snitch was “enough to show the screenshot was authentic. See Fed. R. Evid (b)(1)(4).

In United States v. Quintana, 763 Fed. Appx. 422 (6th Cir. 2019), an account in the defendant’s name, an email address with his name and moniker, a location linked to him, dates that corresponded to witness testimony, and a picture of him, plus other circumstantial evidence, was enough to authenticate a screenshot of a Facebook page presented by the government as the defendant’s.

In United States v. Vayner, 769 F.3d 125 (2nd Cir. 2014), the court did find a screenshot, alone, was not enough. The court expressed no view on what was enough but said that the fact the page with a defendant’s name and photograph existed on the internet was not enough to show the page was created by him or on his behalf.


If the government presents you with a cellphone screenshot and claims your client is responsible, do not accept this at face value! Investigate it, even if it looks legitimate. Check to see if you received the file from the government in a PDF format, versus in an image format consistent with the device that allegedly took the screenshot. In addition, make the argument that the screenshot, alone, or even with other evidence, is unreliable, unauthenticated, and inadmissible. As part of this attack, educate the court and government on how easy it is to create fake messages. This is necessary to remove the gloss of reliability given to a screenshot of a text message that looks like what we are used to text messages looking like.

Because this question incorporates a technical inquiry, it is an area where working closely with an investigator, paralegal, or expert who understands the processes of the device at issue can help you argue to keep something out or let something in. A knowledgeable source can help you identify weaknesses or vulnerabilities to bring attention to during cross-examination. They should also be able to give you a factual assessment of a device’s or processes’ strengths and reliability. Either way, the more you know and understand, the better you can formulate and convey your argument.

Shutter Encoder


Shutter Encoder

We are constantly on the lookout for new tools to keep in our litigation support toolbox and Shutter Encoder is quickly becoming one of our new favorites. It’s a publicly available (a.k.a. “free”) media converter program that is based on standards and functions within the open-source FFmpeg software project. Currently there are both PC and Mac versions available for download from their website:

Here are a few of our favorite things we like to do with Shutter Encoder:  

Convert file formats

Media files come in lots of different formats (ex: .asf, .avi, .mpg, .mov, .wmv, .amr, .m4a, .wav, .wma, etc…). It can sometimes be a struggle to consistently get them all to play. Some files are only compatible with specific programs, operating systems, and devices while others may also require that special “codec” packages be installed. Shutter Encoder can be used to convert media files using “standard” output codecs that work with a wide variety of environments.

For most video files the output codec standard we recommend is an MP4 file using the H.264 standard. This format is compatible with many modern devices, operating systems and video playback applications.

For example, we might have some .ASF video files that play in VLC Media Player, but will not work in Trial Director. When we add these files to Shutter Encoder, choose the H.264 output codec, then select the “Start Function” button, we produce new MP4 copies of the files that will play in both programs.

With audio files, we like to use the MP3 standard when converting as it works seamlessly with most media players. When choosing an MP3 output, you can further select from a list of different audio “bitrates” (in kb/s), which will affect the quality and file size. In most situations, we choose the 128 bitrate as that offers a nice balance between the two.

Cut, Remove and Split

There are many times when only a portion of a media file is needed. To produce a clip, or remove an unwanted section, Shutter Encoder includes Cut, Remove and Split options. We can access these features from a playback screen when converting file formats (ex: after adding a video file and choosing the H.264 Output codec).

The playback screen includes a timeline band (with a waveform graphic overlay), a play control button set, and a Mode selector. To select a portion of the media being converted, click and drag from the left and/or right sides of the timeline band. Alternatively, there are Begin and End buttons within the playback button set that can be used. The Mode dropdown in the lower right includes the following options:

  • Cut converts the selected portion of the media (and ignores unselected parts).
  • Remove takes out the selected portion (and converts unselected parts). 
  • Split (less commonly used) divides media into separate files based on a user defined number of seconds.

We can preview a Cut or Remove section in a separate window by using the “Preview” button located to the right of the Mode dropdown. The actual Cut, Remove or Split will begin once the “Start Function” button is pressed and will only affect the output file (not the original).

Reduce video file size

Larger video files can often be difficult to work with. They can take a long time to open, use up valuable drive space, and prove challenging to share with others.

In addition to the Cut, Remove and Split features listed above, there are “bitrate” adjustments that can be made to video files that affect the size of the output file during conversion. Bitrate settings affect things like the video smoothness and sound clarity. Though the default options work well in most scenarios, it is possible to adjust these settings to create a smaller sized output file. Generally speaking, the following settings allow for a more compact output file size without any noticeable quality losses:

  • Video bitrate: 2500 kb/s
  • Audio bitrate: 128 kb/s

Adjust video rotation

If certain videos (especially those recorded on mobile devices) are not playing back in the correct orientation, we can re-orient them within Shutter by 90 degree increments. When the conversion function is chosen, Image Rotation options appear above the bitrate adjustments on the right panel. The preview window shows how the new orientation will appear in the output file when adjusting these settings.     

Download web video(s)

Another useful function within Shutter is Download Web Video. This will attempt to download available videos from specified webpage addresses (URLs). Though it may not work with all videos on all webpages (due to page design or video protection protocols), it seems to work well with many common sources including Youtube, Vimeo and FaceBook video posts. We can copy and paste one or more URLs and the program will attempt to download the videos to the desktop. We can even point it to a Youtube channel page and to attempt to download multiple videos (if there are a lot of videos on the channel, be mindful that it might take a long time and a lot of hard drive space).

Below is a brief video demonstrating some of the functions mentioned in this post:

When a WOTUS is not Water: Winning the War with TRIAL DIRECTOR


Courtroom technology is a boon for attorneys conducting courtroom presentations. Perhaps its greatest advantage is that the technology allows you to present your theory of the case in a visual way. Research and experience show us that having relevant graphics is more persuasive than words alone.[1] A principal challenge for the defense in criminal cases is that we are reactive to the government. We have to adjust to how the prosecution builds its case in chief when putting on our defense. Trial Director’s[2] greatest benefit for defense practitioners is that it allows them to add a visual component to their cross examination on the fly. This feature is critical, as more often than not we will be unsure how a witnesses’ testimony will come in on direct, and what we may need to focus on during cross-examination. To illustrate how Trial Director can be a useful tool for CJA panel attorneys and Federal Defenders, we will review a real case I worked on, United States v. Lucero, No. 19-10074 (9th Cir. 2021). This trial involved explaining complex scientific and regulatory information to a jury. Let me give you an example of how we used Trial Director and visuals to assist with the cross-examination of witnesses – and then tied it together in closing. I served as the “hot seat” operator, pulling up and annotating exhibits under the attorneys’ direction, as I describe in detail below.

Dumping Debris into a WOTUS

Our client, a dirt broker, was charged with illegally dumping debris onto federally protected wetlands on an undeveloped, privately owned property in Newark, California. This area covers about 400 acres located south of San Francisco near Mowry Slough. It is next to the Don Edwards San Francisco Bay National Wildlife Refuge. At the time of the charged offense, a consortium of developers was in the process of planning a master-planned golf course community on the site.[3] The case was brought under the Clean Water Act, 33 U.S.C. § 1251 et seq. (“CWA”) which made it a crime to discharge pollutants onto wetlands, regulatorily defined as traditional navigable waters, without a permit. At trial, we conceded that our client dumped debris without a permit. The judge denied our requested knowledge instruction, so the government did not have to prove Lucero’s knowledge of the wetland issue. Multiple government experts testified that the dump sites qualified under the regulatory definition as “wetlands.” However, the sites did not appear wet at the time of our client’s conduct, because the dumping occurred during the summer and after several years of drought.

As we shall show below, we were able to set up the issue of knowledge at trial, and eventually won on appeal. Below are a series of brief examples designed to illustrate how we used TRIAL DIRECTOR during the cross-examination of witnesses.

Educating the Jury

The map at Figure 1 was one of the exhibits we used during the cross-examination of a government expert. Initially, this expert was hired by the developers to conduct an environmental analysis of the area. During direct examination, the government showed the expert a series of maps to elicit testimony designed to illustrate precisely where, on the property designated as wetlands, our client dumped debris. These two regions in the map below demarcated with red boundaries were where he dumped debris using dump trucks over a period of several months.

Figure 1
Figure 1

This map included a key indicating which parts of the area were designated as wetland (Figure 2).

Figure 2
Figure 2

During cross-examination of the expert, we used what Trial Director describes as a “callout.” The attorney directed me to zoom in on the portion of the exhibit that had the map key. Using the software program, I drew a box around the map key. The software program pulled out that portion of the exhibit, making it larger, while adding a 3-D fade-black effect on it with projection lines. NOTE: I could adjust the size and shape of the “callout” on the fly, and even scroll within it as needed. The attorney then elicited testimony about how, for example, there were significant segments of the area in question that were not designated as wetland, to support our lack-of-knowledge argument.

Tributaries, Culverts, and Navigable Waters

Figure 3 is another map of the same region, again with red demarcations showing that the area where our client dumped debris was protected wetland, but with additional details such as references to tributaries and culverts.

Figure 3
Figure 3

The map at Figure 4 is a screenshot of what I did live in front of the jury pursuant to the attorney’s instructions. This process was dynamic. The attorney asked me to do a callout, and instructed me to draw arrows to show the areas where our client was accused of dumping debris, within the “South Fill Area and the North Fill Area”.

Figure 4
Figure 4

The crucial fact in dispute was whether this area was considered a WOTUS, and that determination involved the question of whether the TNW had a “tributary;” that is, whether it showed physical features of flowing water. One of the areas of “flowing water” was this culvert. Live, in front of the jury, the attorney instructed me to use the “Zoom Region” tool in Trial Director to allow the jury a closer view of the map detail (Figure 5).

Figure 5
Figure 5

The Presentation screen is a feature of Trial Director that can be used to display multiple pieces of evidence simultaneously.  It is divided into nine zones – Zone 1 is the left side of the screen, Zone 2 is the right side of the screen, Zone 5 is to the top left quadrant, and so forth. We used this feature to address the question of whether the culvert was a WOTUS during cross-examination of a witness. Figure 6 shows the aerial map of the area with the culvert in Zone 1, shown side by side with a video of the general area of the culvert Zone 2, paused to show the culvert in the foreground. The attorney then instructed me to use the annotation tools to add arrows and ellipses to indicate where the video footage of the culvert was in relation to what was shown in the aerial map. (Figure 6).

Figure 6
Figure 6

Figure 7 (below) is an iteration of Figure 6, with the aerial map still on the left side of the presentation screen (Zone 1) while on the right side of the screen (Zone 2) the attorney instructed me to again pull up the same video exhibit. However, instead of the same frame of the clip shown in Figure 6, the attorney instructed me to play the video and then pause it at a point showing a close-up of the water flowing through the culvert. The attorney also instructed me to use the annotation tools to add arrows and ellipses to indicate where the video frame of the culvert was in relation to what was shown on the aerial ma. One related and exciting feature of Trial Director is its ability to do a callout of a portion of a video while it plays. You can zoom in on a specific area of the video, do a callout, and let it continue running to show the zoomed area in detail as it plays. This feature can be particularly useful when playing surveillance or body cam videos.

Figure 7
Figure 7

A Close Reading of Topographical Maps  

One of the government’s witnesses in the Lucero case was a civil engineer who had been involved in conducting a land survey of this area – again, the issue was whether the geological and ecological features of the area met the criteria for it to be considered a WOTUS. We conducted an extensive cross-examination of the civil engineer, during which we closely reviewed a series of topographical maps, such as the one shown in the video below (Figure 8). To effectively pull off this cross-examination, the testimony was tied to a close reading of the topographical maps, focusing on the significance of the gradients indicated by the contours. The ability to dynamically pivot on the fly, depending on how the witness testified, was critical.

Closing Argument

When using courtroom technology, most people will use PowerPoint for opening statements and closing arguments. However, Trial Director can be used for openings and closings as well. Many experienced practitioners will use PowerPoint as their primary tool during a closing, but then switch over to Trial Director to show an exhibit, so as to respond to a point made during the government’s closing, and then switch back to PowerPoint to continue. One of the themes we focused on during closing argument was the government’s experts’ re-writing of history. Reports prepared between 2007 and 2016 by environmental consultants hired by the developers, and by the US Army Corps of Engineers, differed in key aspects with the reports developed by the witness the government hired. For example, the 2007 reports did not find that there were any tributaries, while the government’s expert report determined that the ditches in the South Fill Area were in fact ”tributaries.” (Figures 9 & 10)[4]

Figure 9
Figure 9
Figure 10
Figure 10

Furthermore, between 2012 and 2016, California experienced the most severe drought in a millennium, and the bulk of the pictures introduced by the government at trial were from the 2007 reports and January 2017. We argued these photos of ponding, or water, did not prove water in the summer of 2014, when the charged conduct occurred (Figure 11).

Figure 11
Figure 11

Dumping Debris into “Water”

Our defense hinged on educating the jury about technical issues related to wetlands and the complex regulatory definition of WOTUS. The government had a much easier job, namely, to focus on the seemingly unambiguous visual impact of debris dumped onto this area. Our client was found guilty. (Figure 12.)

Figure 12
Figure 12

On appeal, the United States Court of Appeals for the Ninth Circuit reversed our client’s conviction and vacated his 30-month sentence. It held that the district court erred by not instructing the jury, as the defense had requested, that the government had to prove the defendant’s knowledge that the sites where he dumped debris were “water.” (Figure 13).

Figure 13

The Lucero trial provided an example of how using Trial Director played out in a real case and establishing a factual record for appeal. We were able to demonstrate on appeal with evidence from the record that the knowledge issue was important given how the site appeared dry at the time of the offense. The visuals provided the backdrop for our expert’s declaration, which we submitted as an offer of proof. The appellate court relied on this record to reverse on the knowledge issue.

If the government had opted to retry the case, it would have had to prove that our client knew he was dumping debris into “water” in the generally understood sense of the term, rather than into an area defined as “a water of the United States” within the meaning of the CWA. Ultimately, the government opted not to re-try the case. On October 20, 2021, our client, who had remained out of custody while the case was pending, pled to one CWA count and an agreed-upon sentence of one year probation.

The chart below sets forth practical considerations for using the software in the courtroom (Figure 14).

Figure 14
Figure 14

This blog post was designed to provide an overview of how you can utilize Trial Director. If you would like to take a deeper dive with a hands-on, one-on-one training, please contact Kelly Scribner or Joe Wanzala.

[1] “People learn more deeply from words and graphics than from words alone. This assertion can be called the multimedia principle, and it forms the basis for using multimedia instruction – that is, instruction containing words (such as spoken or printed text) and graphics (such as illustrations, charts, photos, animation, or video) that is intended to foster learning.” (Mayer, 2021, in press-a). See

[2] As of July 2023, IPRO has renamed TrialDirector 360 to TRIAL DIRECTOR. It has also been called Trial Director and TrialDirector (one word) in the past. For the purposes of this post, we will use the term “TRIAL DIRECTOR” and “Trial Director” interchangeably to describe the software program.


[4] In April 2020, the Environmental Protection Agency promulgated a new WOTUS rule which narrowed the definition of ‘waters of the United States’ and found that ditches would not be considered to be “tributaries.” The most current version of the WOTUS rule took effect March 2023, but then there was a subsequent Supreme Court decision limiting/revising the meaning of WOTUS. see,

Traveling Through Time in the Wayback Machine (without Mr. Peabody)

The Internet is a dynamic place. While that is a benefit when we want new information quickly, it is a challenge in the legal field when we need a reliable, stable platform on which to build our arguments or conduct research. This backdrop is where the Wayback Machine comes in. The Wayback Machine is a service provided by the Internet Archive, a non-profit digital library dedicated to the preservation of our digital culture, which contains more than 26 years of archived web pages available for our viewing. This resource can serve our profession in two ways: first, as a tool for researching information that has disappeared from the public-facing internet; and second, as a tool for providing a stable link for use in briefs and motions. There are for-profit entities out there that will charge you for a similar service, however the Internet Archive is free, and has a proven track record of stability.

As a Research Tool

The Wayback Machine gives users the ability to go back and see what a particular webpage looked like on a certain day. For instance, here is this blog from April 27, 2012: Or here’s the front page from the New York Times on February 23, 2016:

How can this be useful? Let’s say that part of your theory of defense hinges on Snapchat’s Privacy Policy in place on June 8, 2019, but if you visit Snapchat’s website at the time of this writing, you will see that the current privacy policy was updated in 2022.

To find the policy in effect on June 8, 2019, you can use the Wayback Machine, by going to and searching for

Once you have selected the correct site, the Machine will take you to a timeline and calendar where you can select the capture for the desired date and time. First, click on the correct year on the timeline, in this example, 2019.

Next, select the date and capture time you want from the calendar. A quick note, captures and dates that are blue are better than green, so go for those if possible.

The Wayback Machine will now load as it looked on June 8, 2019, at the time you selected.

From here, you can navigate to the Privacy Policy and view it as it was on June 8, 2019.

To save it, you can either print it, capture it with software like WebPreserver, or link to it via the Wayback Machine. For more information on this last method, see the next section.

Stable Links for Citation

Citation to internet sources in motions or briefs can be a tricky thing. Sure, the Bluebook can tell you the “proper form” for an internet citation, but no amount of spading today guarantees that a link will work tomorrow. Not only can a website change its structure, rendering the link dead, but the site itself could disappear, taking all its data with it. The Wayback Machine can help.

In the exercise above, we located the Privacy Policy for from June 8, 2019. If you needed to incorporate this page into a brief, you could either print or capture it as a PDF and attach it as an exhibit, or you can cite to the Wayback Machine’s version. This type of use is encouraged by the Internet Archive. After you arrived at the Snapchat’s privacy policy, the address bar shows an exact link to this version of this page.

Simply copy and paste the URL from the address bar into the citation in your brief. Now, when the court glowingly quotes your winning argument in a ruling, future lawyers reading it on Westlaw in ten years can click and read the original source material without encountering a dead link.

But what if the information you want is not on the Wayback Machine yet? Perhaps the website hasn’t been recently archived, or worse, has never been archived? You can trigger the Wayback Machine to take a snapshot of a page on demand, which will give you a stable link to the information you want for citation. To trigger a capture, go back to the Wayback Machine homepage ( Instead of entering a query in the search box, enter the URL you would like to preserve in the “Save Page Now” box.

For instance, this blog had not been archived since January. I entered into the “Save Page” box, and told it to save. After a page where I confirmed what I wanted, The Wayback Machine got to work:

Now the Wayback Machine has a current snapshot. To copy the link, right-click on the “Visit Page” link and select “Copy Link Location” or visit the page itself and copy the URL from the address bar.

As a warning, the Wayback Machine will not work with all websites. Some sites use special settings (robots.txt) to prevent automatic capture or crawling by sites by search engines. For example, individual Facebook profiles are not available. A good rule is if you can’t find it with Google, you probably won’t find it on the Wayback Machine.


As I said in the beginning, the Internet is a dynamic place, but we do not have to let it stop us from finding the information we need or cause us to worry about the citations in our legal arguments. The Wayback Machine can be a blissful island of stability in an ever-changing world. Cite with confidence.

ChatGPT: Implications for Criminal Defense Litigation Practice

eDiscovery, or electronic discovery, is the process of identifying, collecting, and analyzing electronically stored information (ESI) in order to be used as evidence in legal cases. This process can be time-consuming and costly, as it often involves manually reviewing large amounts of data. However, advances in artificial intelligence (A.I.) have opened up new opportunities for streamlining the eDiscovery process. One such technology is ChatGPT, a large language model developed by OpenAI.

ChatGPT is a powerful tool for natural language processing (NLP) that can understand and generate human-like text. This makes it an ideal candidate for use in eDiscovery, as it can quickly and accurately analyze large amounts of ESI in order to identify relevant information. For example, ChatGPT can be used to identify specific keywords or phrases within a document, classify documents by type, or even summarize the content of a document.

The introductory paragraphs above were generated by ChatGPT in response to a request to write a blog post on ChatGPT and eDiscovery. This is an example of how ChatGPT can generate text in such a way that one cannot immediately tell whether it was written by a machine or human. This blog post will provide initial takes on what the potential ramifications ChatGPT and similar Artificial Intelligence (A.I.) tools can be for the work CJA panel attorneys and federal defenders do. It is not advocating any specific position regarding A.I. technology which has wide ranging and yet to be realized implications in many fields. The goal is to provide a general idea of how this new A.I. technology might impact our work.

What is ChatGPT?

The current version of ChatGPT, 3.5 was released in late 2022 ( It is an artificial intelligence tool built on a natural language processing model known as a Generative Pre-trained Transformer (‘GPT’) or ‘generative A.I.’ developed by OpenAI. ChatGPT is great for generating human-like text to help solve problems. This can include answers to questions, summaries or translations of large volumes of text, generating lines of code, or providing step-by-step, conversational instructions for a wide range of complex software applications.

ChatGPT is trained on a massive corpus of datasets including many publicly available domains on the internet including Google, the Wayback Machine, Github, WordPress, Wikipedia, and so forth.  However, it is not connected to the internet in real time and has limited knowledge of world and events after 2021. This means it can occasionally produce inaccurate information, a problem that OpenAI acknowledges In some instances, it will tell you it doesn’t know, sometimes it will provide an answer with a disclaimer. It can also provide an authoritative sounding answer that is wrong without any qualifier. It has even been known to fill in the gap with made up information. For example, eDiscovery expert Ralph Losey asked the robot to identify the top five eDiscovery cases for 2022. Since it did not have any 2022 cases to reference – it ignored the date – listed only 2021 cases, and even made up the name of a judge!

In response to these sorts of user experiences, OpenAI recently sent out a tweet with warnings noting that ChatGPT is useful for general information in subject areas such as language, science, engineering, finance, history, culture; and less suitable for high context or niche areas such as legal advice, and real time events.

Can ChatGPT be used for discovery review?

Artificial Intelligence models based natural language processing have been deployed extensively in eDiscovery for some time. Foremost among these approaches is Technology Assisted Review (TAR)[1] which uses algorithms to identify and highlight relevant information based on input from subject matter experts. This technique helps reduce attorney review time and thereby creating time and cost and workflow efficiencies.

Since TAR and generative A.I. are both based on the natural language processing branch of artificial intelligence (Figure 1), one might assume that ChatGPT’s ability to generate human-like information about a broad and complex range of data sets could be easily applied to eDiscovery to enhance eDiscovery review methods such as TAR. Indeed, in the second introductory paragraph above, ChatGPT generated text that describes common eDiscovery tasks that artificial intelligence software can perform with the proper conditions. But it also wrote that it, ChatGPT, could do these types of tasks. While it is true that ChatGPT can perform these tasks based on information it has been trained on, it was not designed to perform eDiscovery tasks, and OpenAI has not developed a version of the GPT technology that can be utilized for eDiscovery. Furthermore, even if the underlying GPT-3.5 model could be developed for an eDiscovery environment, the immense computing resources it currently requires, designed for vast amounts of data, would make it non-scalable and cost-prohibitive.

Figure 1.

What can ChatGPT do right now?

ChatGPT has more direct application in terms of workflow and analysis. Discovery in criminal cases increasingly includes both structured (databases, spreadsheets) and unstructured (documents, videos, audio files, phone extractions, social media, emails) data. Currently, most workflows designed to integrate and synthesize these heterogenous formats are necessarily cumbersome, requiring a patchwork of approaches. Many easily available open source tools (e.g. Openrefine, referenced below) or applications such as Microsoft Excel which can be helpful to practitioners are under-utilized, if leveraged at all. ChatGPT has the potential to help bridge the gap between the utility of these applications and practitioners’ ability utilize them.

For example, below (Figure 2) is a screenshot showing ChatGPT’s response to a question about importing a CSV file[2] into CaseMap (a fact and case organization and analysis tool – Note that while ChatGPT is providing helpful feedback, it is not providing specific, practical instructions on how to carry out the importation of the CSV file into a CaseMap database. This is due to the limited information about CaseMap built into the OpenAI model. In the example above, ChatGPT was able to provide a step-by-step guide on how to import a CSV file into CaseMap. However, there are better and more efficient ways to import a CSV file into CaseMap than what ChatGPT prescribed.

Figure 2.

In our second example, (Figure 3) we see how ChatGPT can help us deal with, CSV files containing ‘messy’ data, in this case duplicate rows in a spreadsheet. It provided guidance on how to utilize a tool called Openrefine to ‘clean-up’ the spreadsheet.

Figure 3.

Since Openrefine is a free, open source tool, ChatGPT was able to develop more accurate information than one might expect when dealing with ‘closed’, proprietary tools such CaseMap.


The need to harness software to effectively work our cases will only increase as data complexity continues to ratchet up. ChatGPT can help facilitate the utilization and adoption of open source and business applications in response to these challenges; lowering the bar to access by providing on-demand, human-like support to practitioners. This can help with the ‘trees’ we believe are relevant to our cases; e.g. a subset of files responsive to a search query. This still leaves the ‘forest’; the large tranches of discovery which we load into review platforms such as Eclipse SE and Casepoint, to parse and organize the data. Whether or how the generative AI technology underlying ChatGPT will have impact in this latter arena remains to be seen.

[1] Also known as predictive coding, computer assisted review, or supervised machine learning.

[2] A comma-separated values (CSV) file is a delimited text file that uses a comma to separate values. Each line of the file is a data record, and usually consists of tabular data from a database. The CSV file format is supported by a wide variety of business applications including MS Excel

Microsoft Excel Tips & Tricks for CJA Cases: Formatting Tables

This post is part of an ongoing series of videos on how Microsoft Excel can help CJA practitioners (including attorneys, paralegals, investigators, and mitigation specialists) in their CJA cases.

Previous Post: Filename Lists
Today’s Post: Formatting Tables

CJA panel attorneys and federal defenders frequently receive some of their discovery in spreadsheet or Excel format. Call detail records and indices listing information regarding discovery productions (often called document indexes) are two examples. Having the files in Excel format instead of PDF is advantageous as spreadsheets are designed to sort and filter information, either by a single or multiple criteria. With voluminous information, this ability to sort and filter by multiple criteria can speed up review and allow you to identify the information you are interested in. For example, if you have telephone call records in Excel format, it is easy to filter by a number of phone numbers and quickly narrow the entries to review with several clicks. If the same information is in PDF format, it would have to be done manual and take much, much more time.

For those experienced with Excel, it is a welcome sight to see the data in Excel format. However, for the neophyte Excel user who only reviews PDF files, it can be frustrating to navigate Excel and review the data. This post provides quick and easy formatting options that are available within Excel that can save you review time.

Let’s look at a mock discovery document index as an example. Often the document index starts as a simple list of files with some basic information. As these lists become longer and include more document details (frequently in the form of additional columns), they can be hard to read and work with unless formats are applied. The video below demonstrates quick and simple options within Excel that can help to transform a basic list into a better looking, more functional table that include easy to use sort and filter features.


Some of the topics covered in the video above are:

Column Width
It often helps to be able to adjust the width of columns to better fit important information on your screen. To adjust the width of a column:

  • Move the cursor in between the column headers until it becomes a black line with two arrows.
  • To manually adjust the width of a column left-click then drag the black line to the right or left.
  • To automatically adjust a column, double left click and the column width will become as wide as the longest text entry in that column.
  • Multiple columns can be adjusted at the same time by selecting them before making a manual or automatic adjustment.

Wrap Text
Automatically resizing row heights helps to make the words within longer text cells visible. Select the cells, rows or columns to be adjusted then choose the “Wrap Text” button from the Home menu.

Cell Alignment
Adjusting cell alignments can sometime help make items more uniform and easier to view. By default, Microsoft Excel aligns numbers to the “Bottom-Right” of cells and text to the “Bottom-Left”. A common adjustment is to change cells that are “Bottom” aligned to become “Top” aligned, as that is generally easier to read. To do this: select the cells, rows or columns to be adjusted then choose the “Top Align” button from the Home menu. “Right” aligned cells can be adjusted to “Left” alignment through a similar process.

Freeze Panes
Selecting certain columns and rows to always be visible greatly increases the readability of longer lists. To freeze panes:

  • Left click on the cell to the right of, and below the rows and columns you wish to always be visible.
  • From the View menu, click on the “Freeze Panes” button and select the “Freeze Panes” option.

Data Filter
Data filtering is a powerful formatting option. It unlocks the ability to easily sort, filter and search within columns. To turn on filtering:

  • Select all of the data including any column names.
  • From the Data menu, select the “Filter” button.
  • Once data filtering has been enabled, items can be sorted, searched and filtered on by choosing the filter button from the columns.

Format as Table
Alternatively, data can be filtered by selecting a “Format as Table” style. “Table” styles are a quick way to make the data visually pleasing and they automatically include the data filtering feature. To turn a list into a “Table” style:

  • Select all of data including any column names.
  • From the Home menu, click on the “Format as Table” button and select your desired style (I like the “Medium” styles personally).
  • From the “Create Table” dialog box select the “My Table has headers” option then click the “OK” button.

Note: Be aware that these format changes are modifications to the original Excel file. If preserving an original copy of the file is important make sure to choose the “Save As” option when saving changes.

Electronic Exhibit Sticker

Preparing exhibits for trial or court hearings, though not glamorous, is an essential task in the practice of courtroom litigation. Depending on the volume and type of exhibits, this necessary task can quickly turn tedious if you must print each exhibit, affix a physical sticker, fill out the exhibit and case information by hand, then scan and submit the stickered exhibit. In the heat of trial where last minute changes take place frequently, it is easy to make mistakes. However, with the right type of technology, such as Adobe Acrobat Pro (or Standard), this process can be done more smoothly, help reduce opportunities for making errors, and done more quickly than the old school method of stickers and paper  If you have Adobe Acrobat*, we suggest considering using digital (electronic) exhibit stickers for your next case.

*Acrobat Standard or Pro, not the free “Reader” version.

This post will walk you through how you can create digital exhibits on your own, including the process of installing a sticker that takes the form of a custom Acrobat stamp. The stamp will allow you to quickly fill in the exhibit and case numbers for your case, and will automatically remember your previous entries the next time you use it.

First, follow the instructions below to install the electronic exhibit sticker.


  1. Download and copy the exhibit_stickers.pdf file to a location that is easily accessible, such as your Desktop. (NOTE: You can delete this PDF file once we are finished with the installation.)
  1. Open Acrobat and press CTRL-K to open the Preferences menu. Scroll down on the left to “Security (Enhanced)”. Click the “Add File” button, which will open a file explorer window.
  1. Type %appdata% into the address bar and press enter.
  1. This will open a new folder.  Open the “Adobe” folder, then the “Acrobat” folder. You may see folders for the different versions that have been installed like a “2017”, “2020” or a “DC” folder. Open the “DC” folder if you have that, or else the highest folder year you have. Open the “Stamps” folder. Find the “exhibit_stamps.pdf” file you saved and drag or copy and paste it into the Stamps folder. Select the file and click “Open.”
  1. This will take you back to the Preferences screen. Verify that exhibit_stamps.pdf is listed inside the box. If the file is there, click “OK”. Then close out of all Acrobat windows.


  1. Open the PDF that needs an exhibit sticker. Select the “Comment” tool from the list along the right side of the screen.
  1. This will open a new toolbar. Click on the Stamp tool icon, navigate to the “Exhibit Sticker” menu, then click on the Exhibit sticker image.
  1. The first time you use the sticker, it will pop up this window. Check “Don’t show again” and click “Complete.” There is no need to enter any information.
  1. Your cursor will now become a floating exhibit sticker. Click where you would like to place the sticker. Do not worry if the initial placement is not perfect; you can move the sticker to a different part of the page and even resize the sticker after you have placed it.
  1. When you click to place the stamp, a window will pop up asking you to enter an Exhibit Number. Enter the Exhibit number in the box and press OK.
  1. Next, a window will pop up asking you for a Case number. Enter the Case number and press OK.
  1. This will place an exhibit sticker on your PDF that contains the Exhibit Number and Case Number. You can move and resize the sticker if needed. If you need remove or change any of the information on the sticker, you can right click on the sticker, select “Delete” and create a new sticker.
  1. To permanently affix the sticker to the document, you will need to print the document to a new PDF. Go to the File menu and select Print. Now change your printer to “Adobe PDF”, change the “Comments & Forms” selection to “Document and Stamps”, then press print and save your new copy to the location of your choosing.
  1. That’s it. You will now have a permanently stamped PDF document. The next time you want to stamp a document, Acrobat will pre-fill your last enter Exhibit Number and Case Number, so it will be easier to keep track of your exhibits if you are marking multiple documents in one sitting, and you will not have to re-enter the case number each time.

If you need any assistance with installation, you can contact me at

Working with Email in Discovery: Processing Options and Review Workflows


Technologies that allow for easier review of ediscovery in native format have become more affordable and accessible. Working with files in native format has several advantages including avoiding loss of potentially relevant information, access to metadata and better searchability. Email is one of the most common of the native formats produced in discovery. This article will explore some approaches for processing email and identify a number of low-cost of tools that can assist. (This article deals with the processing but not the substantive review of emails for case analysis – for this you should consider other tools such as CaseMap, or – for larger collections of emails – review platforms such as Casepoint or IPRO.)

The tools and approaches you select will depend on a combination of three factors: (1) volume, (2) format(s) and (3) the defense team goals. While a single tool might facilitate a discreet goal, more involved goals may require different approaches with a combination of tools. These scenarios can be ends in themselves or phases in an overall workflow. This article does not try to anticipate every possible situation that might arise but will explore a few common scenarios.

Many electronic file formats produced in the course discovery like Acrobat, Excel and Word files are generally accessible via standard software available on most computers. However, email file formats like MSG, EML, PST, and MBOX files present more of a challenge as often the recipient may not know how to access these files. 

Below is a quick overview of some of the most common email file formats encountered in eDiscovery that will be discussed in this article:

  • MSG: A Microsoft format for single emails. Often associated with the Microsoft Outlook email client.
  • PST: A Microsoft format for a collection of emails (as well as other potential items including: Calendars, Contacts, Notes and Tasks). Often associated with the Microsoft Outlook email client.
  • EML: Email format for single emails used by many email clients including Novell GroupWise, Lotus notes, Windows Mail, Mozilla Thunderbird, and Postbox.
  • MBOX: Email format for a collection of emails (as well as other potential items including: Calendars, Contacts, Notes and Tasks) used by many email clients including Novell GroupWise, Lotus Notes, Windows Mail, Mozilla Thunderbird, and Postbox.

All four formats are typically received in discovery and subpoena returns. Google Takeout, a service offered by Google which allows you to download your email, will produce emails in the MBOX format.

Working with these email formats consists of understanding which tool is compatible with which file format, and which tool or set of tools will most effectively allow you to achieve your goals. Below is a table that maps out some of various tools available in terms of which file formats they are able to process, their functionality and cost. Before using any of these tools, make sure to work with a copy of the data as opposed to the original.

SoftwareCompatible FormatsCostFunctionality
Mozilla Thunderbird with the Import Export Tools add-onEML, MBOXfreeView emails, convert to EML, HTML, MBOX and PDF (without attachments)
Mbox ViewerEML, MBOXfreeView emails, convert to HTML or PDF (without attachments)
PSTViewer ProMSG, EML, PST, MBOX$129View emails, convert to multiple formats including EML, HTML, MBOX and PDF (includes advanced PDF attachment image options)
MS Outlook  MSG, EML, PST$159 or $69.99 per yearView emails, export to MSG, PST and PDF (requires Acrobat integration)
Aid4MailMSG, EML, PST, MBOX$299 per yearConvert email to multiple formats including MSG, HTML, EML, PST, MBOX and PDF
dtsearchMSG, EML, PST, MBOX$199 or *free
Search and view results in email viewer panel (no conversion or export options)

*For information about a free license of dtSearch available to CJA Panel Attorneys see:

This article will discuss demonstrate how to work with emails in terms of a series of discreet tasks including:

  1. Generate a list of emails to review.
  2. Viewing emails.
  3. Search, tag, and convert emails.
  4. Working with email attachments.

1. Generating a list of emails for review.
An initial task at the outset of a case might be to generate an index to facilitate early case assessment. Some programs, like PstViewer Pro, will work with many formats while other programs, like Mbox Viewer, work with a more limited number of formats.

  • Example 1 – Generating a list using Mbox Viewer:
    Mbox Viewer is a free tool that allows you to preview emails and generate a list of emails by simply selecting messages in the viewer, doing a right click and selecting print to CSV, then selecting which fields you would like to include in the spreadsheet (Figure 1-1).
Figure 1-1
  • The resulting CSV file contains a table that can be opened in Excel or imported into other programs (Figure 1-2).
Figure 1-2

2. Viewing emails.
While a list will provide you with a high-level overview of the emails you have in terms of subject matter, players involved and so forth, a closer review will require a different approach. MS Outlook, Mbox Viewer and Mozilla Thunderbird are all tools which can be utilized for this purpose.

  • Example 2.1 – Viewing emails received in PST format using MS Outlook:
    Within Outlook open the ‘File’ menu, select the ‘Open & Export’ button, then ‘Open Outlook Data File’. Navigate to the folder containing the PST file (Figure 2-1) and select the file to import. Outlook will create a folder within the ‘Personal folders’ from where you can conduct a review of the files.
Figure 2-1
  • Example 2.2 – Viewing emails received in MBOX format using Mozilla Thunderbird with the Import Export Tools add-on:
    The free ‘Import Export Tools’ add-on available for Mozilla Thunderbird allows for the import and viewing of MBOX files. After the add-on has been installed, right click on ‘local folders’, then choose ‘Import mbox file’ from the ‘ImportExportTools NG’ menu and navigate to the folder containing the MBOX file (Figure 2-2). This will copy the MBOX file into Thunderbird’s ‘Local Folders’ where, similar to Outlook, you can conduct a review of the emails within.
Figure 2-2

3. Search, tag, and convert emails
The approaches discussed in the two previous sections can be useful when you simply want to gain a high-level view of the emails, or take a closer look at particular emails in a smaller collection. However, when you are working with large volumes of emails, manual review becomes impractical and inefficient, and taking advantage of the search and tag functionality of the available tools is a better approach.

  • Example 3 – Searching, tagging and exporting within MS Outlook:
    Outlook can be utilized to conduct key word searches, and relevant files can be tagged exported as either MSG or PDF files (using the Acrobat integration that is included with licensed copies of Acrobat Standard and Pro). To tag an email, right click and select ‘Categories’ then select a color coded tag (Figure 3-1). You can also customize the tags using the ‘New Category’ option within the ‘Category’ dialog box (Figure 3-2).
Figure 3-1
Figure 3-2
  • You can then filter and tag a selection of emails (Figure 3-3) and save them to a folder as either individual MSG files or a new PST file. If you have a licensed version of Adobe Acrobat, there integration menu within Outlook can be used to convert messages into individual PDF’s or a combined ‘PDF Portfolio’ (Figure 3-4).
Figure 3-3
Figure 3-4
  • When choosing an export format, be aware of the limitations of the different conversion formats. The HTML and PDF export formats typically will not include the complete email metadata. Email header information that may include important information like IP addresses used may be lost during conversion. Export formats including the MSG, EML, MBOX and PST retain much more of the original email metadata.

4. Working with email attachments.
Emails invariably have attachments, which, in addition to the body of the email can contain substantive relevant information. The programs discussed in this post vary greatly with how attachments are handled during format conversion. Be aware that some of the programs are not able to include the attachments when exporting to PDF. While PDFs are generally easier to add bates stamps to or turn into exhibits not all programs include the attachments..

  • Example 4.1 – Exporting email with attachments using Mozilla Thunderbird with the Import Export Tools add-on:
    Thunderbird offers several export options including the ability to batch export relevant emails when using the Import Export Tools add-on. It does not have the ability to embed or append attachments when exporting messages to PDF, however it does allow for emails to be exported to the EML format (with attachments embedded) as well as an HTML format, which will include links to exported copies of the attachments (Figure 4-1).
Figure 4-1
  • Example 4.2 – Exporting email with attachments using PSTViewer Pro:
    PSTViewer Pro is yet another option for format conversion, and is a great tool to use in conjunction with tools like Thunderbird or Outlook. It can convert to many formats and includes some advanced PDF conversion options. When converting to PDF, attachments can either be embedded or “imaged” (Figure 4-2). The “imaged” option will convert supported attachments into PDF pages and appended them to the PDF version of the email (Figure 4-3).
Figure 4-2
Figure 4-3


As shown in this article there are a multiplicity of tools available to work with emails that are not universally compatible with all email formats and do not have the same functionality. This requires careful thought about how to leverage and integrate the tools. The best path forward through this thicket is to know what your goals are before you select your tool. Defining your goal early will help you select which tool or combination of tools you should use to develop an effective workflow that matches both the set of data you are working with and the needs of your case.

Google Data and Geofence Warrant Process

[Editor’s Note: John C. Ellis, Jr. is a National Coordinating Discovery Attorney for the Administrative Office of the U.S. Courts, Defender Services Office. In this capacity, he provides litigation support and e-discovery assistance on complex criminal cases to defense teams around the country. Before entering private practice, Mr. Ellis spent 13 years as a trial attorney and supervisory attorney with Federal Defenders of San Diego, Inc. He also serves as a digital forensic consultant and expert.]


This is an updated version of a post originally published in December 2020, which provides a primer on how Google collects location data, the three-step warrant process used by law enforcement to obtain these records, and an example of how the data is collected and used by the prosecution. The updated version includes references to United States v. Chatrie, a recently decided district court opinion regarding the constitutionality of geofence warrants.[i] From the opinion and the pleadings in Chatrie, we have a better understanding of the Google collection and geolocation search warrant process.

What Can Google Do?

Google began collecting location data in order to provide location-based advertisements to its’ users. Google tracks location data from the users of its products, including from consumers who use Android telephones and those who use Google’s vast array of available apps on other devices such as Apple iPhones. For Android devices, Google is constantly tracking devices whenever the permission settings on the device are set to allow for the use of Google Location Accuracy. For iOS users, location information is only collected when a user is using a Google product, such as Google Maps.[ii] Google stores this information in a repository called “Sensorvault”, which “assigns each device a unique device ID…and receives and stores all location history data in the Sensorvault to be used in ads marketing.” 3:19-cr-00130-MHL at 7. The use of Sensorvault has been very profitable for Google. Since Google started collecting data and using Sensorvault in 2009, Google’s advertisement revenue has almost increased tenfold.


Google is able to determine the approximate location of a mobile device based on GPS chips in the device, as well as the device’s proximity to Wi-Fi hotspots, Bluetooth beacons, and cell sites.[iii] For purposes of Wi-Fi, Google uses the characteristics of wireless access points within range of the device (including received signal strength) to determine the device’s proximity to the access point, and thus approximate location. How Google tracks this data is dependent of the type of device (Android v. Apple) and an individual user’s privacy settings.[iv] Google cannot determine the exact location of a device, and as such, location records contain an “uncertainty value” which is expressed in meters.

Maps Display Radius:

Because Google does not know a device’s precise location, it represents the possible location in a sphere, or what Google refers to as the Maps Display Radius.

In this picture, Google’s “goal is that there will be an estimated 68% chance that the user is actually within” the spherical representation.[v]

To see how Google determines the approximate location of a mobile device, viewing the Location History of a Google account is instructive. In the following example, according to Google, the blue line indicates the path of travel, the orange dots represent wireless access points, and the grey sphere next to the blue arrow is the estimated range of the location source.

Generally, the location information source has the largest impact on the Maps Display Radius. Most often, GPS provides the smallest sphere whereas Cell Sites are generally the largest. By way of example, the map display radius for GPS is often a few meters whereas Wi-Fi is routinely over 1000 meters.

Use of Google’s Tools by Law Enforcement – Three-Step Warrant Process

Although the original intent of Google’s Sensorvault technology was to sell advertising more effectively, over the past few years this data has been sought by law enforcement to determine who was present in a specific geographical area at a particular time, for example, when a crime was committed. These warrants are often called “Geofence warrants” because officers seek information about devices contained within a geographic area. In 2021, Google released information about the number of geofence warrants sought by law enforcement. According to the data, “Google received 982 geofence warrants in 2018, 8,396 in 2019 and 11,554 in 2020.”[vi]

In current practice, Google requires law enforcement to obtain a single search warrant. The three stage warrant process is based on an agreement between Google and the Department of Justice’s Computer Crime and Intellectual Property Section (CCIPS). Once Google receives a geofence warrant, it takes on the extrajudicial role of determining when law enforcement officers have complied with probable cause such that additional information will be provided.

Stage One:

In response to the warrant, “Google must ‘search … all [Location History] data to identify users’ whose devices were present within the geofence during the defined timeframe” and to provide a de-identified list of such users. Chatrie at 19. The list includes: (1) anonymized user identifiers; (2) date and time the device was in the geofence; (3) approximate latitude and longitude of the device; (4) the maps display radius; and (5) the source of the location data.[vii]

Stage Two:

After reviewing the initial list, law enforcement can return to Google and request additional information about any device that is within in the first geofence. This includes “compel[ling] Google to provide additional…location coordinates beyond the time and geographic scope of the original request.” Chatrie at 21.[viii]  Troubling,
Google imposes “no geographical limits” for Stage Two review. Id.

Stage Three:

The third step involves compelling Google “to provide account-identifying information for the device numbers in the production that the government determines are relevant to the investigation. In response, Google provides account subscriber information such as the email address associated with the account and the name entered by the user on the account.”[ix]

It is important to note that in practice it appears that law enforcement routinely skips Stage Two and moves directly from Stage One to Stage Three analysis.

Past Examples

The shape of Google Geofence warrants has changed over time. For instance, In the Matter of the Search of information that is stored at premises controlled by Google, 1600 Amphitheatre Parkway, Mountain View, California 94043, law enforcement officers investigating a bank robbery sought information about “all Google accounts” located within a 30 meters radius around 43.110877, -88.337330 on October 13, 2018, from 8:50 a.m. to 9:20 a.m. CST.

Compare that to In the Matter of the Search of Information Regarding Accounts Associated with Certain Location and Date Information, Maintained on Computer Servers Controlled by Google, Inc.. In that instance, law enforcement was investigating a series of bombings and they sought location information for “all Google accounts” for a 12-hour period between March 1 and 2, 2018 in a “[g]eographical box” around 1112 Haverford Drive, Austin, Texas, 78753 containing the following coordinates: (1) 30.405511, -97.650988; (2) 30.407107, -97.649445; (3) 30.405590, -97.646322; and (4) 30.404329, -97.647983.

More recently, Google has requested that law enforcement submit Geofence warrants that are convex polygons in shape.

Starting from the Beginning – How the Process Works

To put this into perspective, the following example is illustrative. For these purposes, a crime occurred in the parking lot of a strip mall.

Because the crime occurred in the middle of a parking lot, we will create a geofence that includes storefronts because it will increase the chances that the suspect’s mobile device will be within range of a Wi-Fi hotspot or Bluetooth beacon. Conversely, the geofence will include the mobile devices of numerous people who are not connected to the offense.

The above geofence appears to only impact people who are present in the parking lot or surrounding business. However, the geofence would likely capture many more people, including people living or visiting in the nearby apartments and anyone who was driving on the surrounding streets during the time in question.

Stage One—The following is an example of a Stage One warrant return:

Device IDDateTimeLatitudeLongitudeSourceMaps Display Radius (m)

Here, Device ID 123456789 is Suspect One, Device ID 987654321 is Suspect Two, and Device ID 147852369 is Suspect Three.  For this example, only one location for each device is shown.

At first blush, it would appear as if the Geofence has located three possible suspects.  But this image does not tell the full story. The blue bubbles for Suspect One and Suspect Two show a Maps Display Radius of 5 and 25 meters respectfully.

Suspect Three’s location was derived from a Cell Site, with a Maps Display Radius of 1000 meters.

Thus, although Google believes that Suspect Three’s device was near the scene of the crime, it is possible it was located anywhere within the larger sphere, and it is possible that the device was not located within either sphere.

Stage Two—For this stage, we can expand our original results, as long as we only include one of the accounts returned in Stage One. Here, we will expand our results and determine if Suspect One’s device also present in the area Northeast of the original search location.

Stage Three—is the step whereby subscriber information about the accounts Google deems responsive. Meaning, law enforcement requests Google to provide the account number and information for Device IDs provided in either Stage One or Two. The following is an example of such a return:

Conclusion As technology and privacy concerns of consumers continue to change, so will the ability for law enforcement to obtain location data of users. The use of Google geofence warrants implicates a number of Fourth Amendment issues; future posts will explore the legal implications surrounding the overbreadth of these warrants.[x] But beyond the legal challenges, those encountering Google location warrants should remain mindful of the limitations of the data as well as the absence of concrete answers from Google regarding their methodology for determining location data

[i] See United States v. Chatrie, 3:19-cr-00130-MHL, Docket Entry 220.

[ii] The exception is for a user who has turned location services to always on, has a Google product open on a device, and has allowed for background app refresh. That means that is likely that Google knows far more about the location history of android users than iPhone users. That’s important because approximately 52 percent of devices on mobile networks are iOS devices.

[iii] (“On most Android devices, Google, as the network location provider, provides a location service called Google Location Services (GLS), known in Android 9 and above as Google Location Accuracy. This service aims to provide a more accurate device location and generally improve location accuracy. Most mobile phones are equipped with GPS, which uses signals from satellites to determine a device’s location – however, with Google Location Services, additional information from nearby Wi-Fi, mobile networks, and device sensors can be collected to determine your device’s location. It does this by periodically collecting location data from your device and using it in an anonymous way to improve location accuracy.”)


[v] See United States v. Chartrie, 19cr00130-MHL (EDVA 2020), ECF 1009 [Declaration of Marlo McGriff] (“A value of 100 meters, for example, reflects Google’s estimation that the user is likely located within a 100-meter radius of the saved coordinates based on a goal to generate a location radius that accurately captures roughly 68% of users. In other words, if a user opens Google Maps and looks at the blue dot indicating Google’s estimate of his or her location, Google’s goal is that there will be an estimated 68% chance that the user is actually within the shaded circle surrounding that blue dot.”)


[vii] Id. at 4 (“After that search is completed, LIS assembles the stored LH records responsive to the request without any account-identifying information. This deidentified ‘production version’ of the data includes a device number, the latitude/longitude coordinates and timestamp of the stored LH information, the map’s display radius, and the source of the stored LH information (that is, whether the location was generated via Wi-Fi, GPS, or a cell tower)”).

[viii] Id. at 17

[ix] Id.

[x] In the Matter of the Search of: Information Stored at Premises Controlled by Google, 20mc00392-GAF (NDIL 2020) provides a great overview of the Fourth Amendment issues relating to Google Geofence warrants.  See also

U.S. v. Morgan, et al: Know What You Don’t Have

[Editor’s Note: Tom O’Connor is an attorney, educator, and well respected e-discovery and legal technology thought leader. A frequent lecturer on the subject of legal technology, Tom has been on the faculty of numerous national CLE providers and has taught college level courses on legal technology. He has also written three books on legal technology and worked as a consultant or expert on computer forensics and electronic discovery in some of the most challenging, front page cases in the U.S. Tom is the Director of the Gulf Coast Legal Technology Center in New Orleans, LA ]

If you were practicing in federal court before email, ECF filing, and in the days when Joe Montana threw to Jerry Rice then you probably remember discovery productions were typically hardcopy documents you picked up at the US Attorney’s Office. The volume was so small it easily fit into your briefcase. Those were the days when everyone complained about not getting enough discovery. The challenge was moving to compel for more discovery when you didn’t know what you didn’t have.

Joe Montana and Jerry Rice

Fast forward to the present. Tom Brady is throwing to Rob Gronkowski (again but in a different city) and discovery is typically so voluminous it cannot be provided in hardcopy form. Productions can be hundreds of gigabytes and sometimes dozens of terabytes full of investigative reports, search warrant pleadings, surveillance audio and video, cell phone data, cell tower material, years of bank records, GPS data, social media materials, and forensic images of servers, desktop computers, and mobile devices. Common are duplicate folders of discovery produced “in the abundance of caution” to protect the Government against Brady violations. Despite the volume, the same issue exists: How do you know what you don’t have?

Tom Brady and Rob Gronkowski

US v Morgan (Western District of New York, 1:18-CR-00108 EAW, decided Oct 8, 2020) is an example of diligent defense counsel challenging the government on how it produced terabytes of data.

Defendants Robert Morgan, Frank Giacobbe, Todd Morgan, and Michael Tremiti were accused by way of a 114-count Superseding Indictment of running an illegal financial scheme spanning over a decade. The government alleged they defrauded financial institutions and government sponsored enterprises Freddie Mac and Fannie Mae in connection with the financing of multi-family residential apartment properties that they owned or managed. There were also allegations of related insurance fraud schemes against several of the defendants.

The government made several productions which the defense contended were deficient (including the lack of metadata on numerous documents) and, in several cases, omitted key pieces of evidence. The defense enlisted the help of e-Discovery experts, who stated the government failed to properly process and load evidence into their database for production to defense counsel.

The issue was brought before the court in defense motions to compel and dismiss. First to the magistrate judge then to the district court judge, which resulted in a critical analysis of the way the government handled the discovery.


The original status conference in the case was held on May 29, 2019. For the next year, a series of motions and hearings proceeded with regards to delays and failures on the part of the government to meet discovery deadlines imposed by the court.

An evidentiary hearing was finally held before district court Judge Elizabeth A. Wolford on July 14, 2020, continuing through the remainder of that week until July 17, 2020, and then resumed and concluded on July 22, 2020. There were multiple expert witnesses, and the review of that testimony is over 7 pages in the Opinion.

On September 10, 2020, oral argument on the motions to compel and dismiss was heard before Judge Wolford. The Court entered its Decision and Order on October 8, 2020.

There was no dispute that the discovery in this matter was not handled properly. In the second paragraph of the above cited Decision and Order, Judge Elizabeth A. Wolford states,

“The Court recognizes at the outset that the government has mishandled discovery in this case—that fact is self-evident and cannot be reasonably disputed. It is not clear whether the government’s missteps are due to insufficient resources dedicated to the case, a lack of experience or expertise, an apathetic approach to the prosecution of this case, or perhaps a combination of all of the above.”

Specifically, the government somehow failed to process and/or produce ESI from several devices seized pursuant to a search warrant executed in May 2018 and in one case, a cell phone, seems to have actually been lost. The court ultimately dismissed the case without prejudice. This gave the parties time to resolve the discovery issues. On March 4, 2021, a grand jury returned a new 104 count indictment.

More important for our purposes are the discussions regarding the ESI and production issues. They are outlined below.


The Court wasted no time in saying “It is evident that the government has demonstrated a disturbing inability to manage the massive discovery in this case, and despite repeated admonitions from both this Court and the Magistrate Judge, the government’s lackadaisical approach has manifested itself in repeated missed deadlines.”

And later, “To be clear, the Court does not believe the record supports a finding that any party acted in bad faith. Rather, the discovery in this case was significant, and the government failed to effectively manage that discovery. In the end, because of its own negligence, the government did not meet the discovery deadline set by the Magistrate Judge.”


Judge Wolford made several references to the “massive discovery.” In an attempt to manage that data, the Magistrate Judge had initially directed the parties to draw up a document entitled “Data Delivery Standards” (hereinafter referred to as “the DPP”) which would control how documents were exchanged. It failed to do so for several reasons.

First was the large amount of data. Testimony by a defense expert witness at the evidentiary hearing of July 14, 2020, stated that “… the government’s Initial Production consisted of 1,450,837 documents, reflecting 882,841 emails and 567,996 other documents. Of those documents, 860,522 were missing DATE metadata, with over 430,000 documents reflecting no change in the DATE metadata field formatting after the DPP was agreed-upon. Once overlays were provided by the government, the DATE metadata field was corrected for almost one-third of the documents (primarily emails), but 590,448 documents still were missing DATE metadata, including 294,818 emails. Of those 294,818 emails, 169,287 had a misformatted DATE value and 125,531 had no DATE value. The Initial Production also contained missing values for the metadata fields of FILE EXTENSION, MD5 HASH, PATH, CUSTODIAN, MIME TYPE, and FILE SIZE— and the government overlays did not change the status of the information in any of those fields.”

Additionally, the USAO-WDNY’s processing tool was Nuix while another entity—the Litigation Technology Support Center in Columbia, South Carolina – processed some of the hard drives using a different processing tool called Venio. Additionally, the Federal Housing Finance Agency (“FHFA”) processed the Laptop Production using a “much more robust” version of Nuix than the system possessed by the USAO-WDNY.

These differing versions led to different productions which had different values for the metadata fields. Standardization on one tool could have prevented much of this. But the Court also noted that “… the quality review conducted by the government was insufficient to catch these errors.”

Inconsistent directions were an ongoing issue. For example, the Court found that “… the government prosecutors expressly instructed Mr. Bowman not to produce CUSTODIAN information for the Laptop Production, even though the government had provided similar information previously.”

Other government errors included:

  1. It applied different processing software inconsistently to the PST or OST files, thereby missing some metadata and producing varying results.
  2. It misformatted the DATE metadata caused by failing to catch the errors while conducting a quality review.
  3. It failed to produce native files in “the format in which they are ordinarily used and maintained during the normal course of business[.]” It produced near native or derivative native files from the OST or PST files without corresponding metadata.
  4. In many instances, load files necessary to install the document productions in the defense review software platform were missing.
  5. There were ongoing errors with respect to CUSTODIAN metadata, which were the result of human error on the part of the government.


With regards to what specific steps can be used to take control of cases with large amounts of ESI, the Court mentioned several.

  1. Use an exchange protocol. In civil cases, this document would arise from FRCP Rule 26(f), which mandates a “Meet & Confer” conference of the parties so that they might plan for discovery through the presentation of a specific plan to the Court. 

    In Morgan, this was the document entitled the DPP. In criminal cases going forward, the new Federal Rule of Criminal Procedure 16.1 will address some of these concerns. Drawn up specifically as a response to deal with the manner and timing of the production of voluminous Electronically Stored Information (ESI) in complex cases, Subsection (a) requires the prosecution and defense counsel to confer “[n]o later than 14 days after the arraignment…to try to agree on a timetable and procedures for pretrial disclosure under Rule 16.1.” Subsection (b) authorizes the parties, separately or together, to “ask the court to determine or modify the time, place, manner or other aspects of disclosure to facilitate preparation for trial.”

  2. Standardize the use of technology. As Judge Wolford said, “In sum, the Court believes that it would have been much more prudent if the government, after reaching agreement with the defense about the DPP, had utilized a competent vendor to process the ESI (and all the previously produced ESI) in the same manner with the same settings and utilizing the same tools.”

  3. Get a data manager. A common saying in IT circles is that “someone needs to own the data.” In this case, where the Government used multiple parties who employed different tools to work with the data, nobody owned the data. This lack of a central manager “… led to electronic productions being produced in an inconsistent manner and, in some instances, in violation of the DPP.”

  4. Get an expert. After hearing multiple experts testify for several days on what had transpired with the ESI, the Court noted, “… electronic discovery is a complicated and very technical subject. As a result, facts can be easily spun in a light most favorable to one party’s position or the other. That occurred here on behalf of all parties.”

    Nonetheless, the experts were able to bring clarification to the issues of “missing” metadata and divergent processing results that had beleaguered the parties and the Court. This field, especially with large amounts of ESI, is a classic example of the old maxim, “do not try this at home.” Get an expert.

  5. Use a review tool. ESI in these large amounts are simply not able to be reviewed manually. Both parties here recognized that fact and, as the Court noted several times, most of the errors in the case were not due to software but what we nerds call the “loose nut on the keyboard” syndrome.

    Get review software. Get trained on it. Use it. One admonition I always make which could have avoided many delays in this matter is do not try to load everything at once into your review platform. Start with a small amount of sample data to be sure you are getting what you need. Which leads to our last takeaway.

  6. Talk with the government. Judge Wolford specifically noted that the “… the Court also concludes that Defendants and the government were not always communicating effectively regarding electronic discovery.” For example, none of the parties could recall “… any discussions during those negotiations about the processing tools that would be utilized or the type of native file that would be analyzed for purposes of creating a load file.”


The Morgan case illustrates there are ways to learn about what you don’t have so you can bring it to the government’s attention and if need be, to the Court. It is also example of a Court being knowledgeable about ESI productions. The Court noted often and in different ways that “… electronic discovery is challenging even under the best of circumstances. In other words, the facts and circumstances cannot be appropriately evaluated without considering the volume of discovery and the enormous efforts needed to manage an electronic production of this nature.”

Find an expert who understands your needs and has effective communication skills to convey to you, the government, and Court complex technical issues. For many years, Magistrate Judge Andrew Peck (SDNY, Retired) advocated “Bring-Your-Geek-To-Court Day,” in which parties bring an outside consultant or an in-house IT person to address disputes. If you were to remember only one thing form this case, it should be: Go get a geek.

Tom O’Connor
Gulf Coast Legal Tech Center 
Twitter: @gulfltc