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How to Effectively Use an Expert Witness to Explain Complex Technical Concepts at Trial : Lessons Fr

It’s been about 4 months since the historic acquittal of Noor Salman in the Middle District of Florida. I’ve had some time to reflect on my work on the case and want to share what I’ve learned about how to effectively present expert testimony on technologically complex issues at trial. Having been in the trial counsel seat (in other cases) and on the witness stand, I’ve learned a lot about how to effectively present expert testimony. It also helps that in the Salman case I had the pleasure of working with (and learning from) some of the best trial lawyers in the country.

Compared to some of the other cases I’ve worked on (e.g., Silk Road), I would not describe the Salman Case on the whole as technologically complex. However, there were certain very critical aspects of the case where the underlying evidence was technologically complicated. This is true in just about any case these days. If you don’t think so, you’re probably missing something. The purpose of this post is to provide some insight into the effective use of experts to explain technologically complex facts to the jury at trial, through the lens of my experience as an expert witness in the Salman trial. It’s not legal advice.

Qualities of an Effective Expert Witness

An effective expert witness MUST have the ability to break down complex technical concepts and explain them in a meaningful way to jurors. That is, after all, the entire purpose of putting on an expert witness at trial. The ability to do so requires a combination of qualities.

1) Intelligence. The expert has to be smart in their field. This is a given. If it appears that they don’t know their stuff, a jury is going to immediately discredit them. However, you can have the “smartest” expert witness, but if they’re unable to effectively communicate the application of their expertise to the facts in a particular case, it’s not going to do you (or your clients) any good.

2) Effective communicator. This is the skill that separates the wheat from the chaff. When I took the stand in the Salman case, I was channeling all of my prior experiences teaching CLE’s, arguing motions, trying cases, all of which served as the basis for my ability to walk the jury through some of the technologically complex concepts at issue. I put together a 30-slide presentation to break down my analysis and conclusions which was basically my entire direct examination (other than the foundational aspect). There has to be a certain rhythm to the presentation in order to be effective; it should be very logical and concise and use demonstratives as much as possible. It can be difficult to condense 250+ hours of work into a cohesive slideshow presentation, but that’s what needs to be done with technically complex cases. Every case is so different, which makes it impossible to lay out some kind of cookie-cutter blueprint that can be followed in every case. You need to have confidence that the expert you select is able to get the job done well.

As an example, part of what I explained to the jury were my findings related to the Pulse Nightclub web server. No doubt, most, if not all of the jurors had no clue about what a web server was or how it works. But I broke it down for them using diagrams and excerpts of the server logs along with practical examples of why a web server would log certain information (e.g., a user agent string). I also remember that on my direct Charlie Swift asked me “how big is a terabyte” so I gave the jury a number in gigabytes, and also explained to them that if you went out and bought 4 of the newest iPhone X’s with 256GB storage, you’d have a terabyte. That’s much easier conceptually than “1,000 gigabytes”

Another character trait of an effective communicator is essentially an ability to “read the room” or in the case of an expert witness, read the jury. No matter what, jurors are going to have varying levels of interest and attention at different points throughout the course of a single witnesses testimony, and certainly throughout the course of a trial. While I was going through my presentation, I was doing my best to scan the jurors faces to gauge their interest and attention. There was one juror in particular who was very very engaged with my testimony and I almost felt as if I was having a conversation with him (although its a one way conversation) he was taking notes and made constant eye contact with me. Testifying as an expert is like being a teacher, you want to recognize the students that are the most interested and engaged because they’ll get the most out of your class.

Which leads to the next point, what is trial counsel’s role in directing their own expert?

Its actually quite simple: do as little as possible. One of the finest trial lawyers I know told me that but for the rules of evidence, he’d ask his experts just one question and sit down: What’d you find in this case? Then let them take it away.

This can be difficult for defense lawyers who are so used being the star on cross-examination, but it’s a completely different dynamic. Save your words for when you’re on cross, where you should never waste a question (which may be the title of a future blog post).

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