Self-Defense Trials And Expert Witnesses

Understanding the strategy of using an expert witness in a self-defense trial.

One of the most misunderstood aspects of a self-defense trial, and the legal strategy that goes into it, is the role of the expert witness.

Federal Rules of Evidence, 702 states:

A witness who is qualified as an expert by knowledge, skill, experience, training or education may testify in the form of an opinion or otherwise if:

• (a) the expert’s scientific, technical or other specialized knowledge will help the trier of fact to understand the evidence or to determine a fact in issue;
• (b) the testimony is based on sufficient facts or data;
• (c) the testimony is the product of reliable principles and methods; and
• (d) the expert has reliably applied the principles and methods to the facts of the case.

This means two hurdles must be met.

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First, the proffered expert witness must be able to be accepted by the judge as being a person who possesses advanced knowledge of a particular aspect of the case, and that knowledge must be used to educate the jury as to a facet of the case that the layperson (most jurors) would not know of or understand.

A perfect example of this is DNA evidence, with the expert witness brought into court to help the jury understand what it means in the case at bar. When it comes to scientific evidence such as DNA or ballistic interpretation of gunshots, usually the state/prosecution will utilize local police detectives, who are paid for by the department and usually in the pocket of the prosecutor.

So, in most cases of murder or manslaughter, the defense must hire an expert—someone who is likely an ex-cop or ex-homicide investigator and has the formal training to stand toe-to-toe with the police detective and give the interpretation to the evidence that’s favorable to the defense.

Primary Objectives

Recently, I was contacted by a public defender who wanted to hire me for a murder case. In this case, the issue to opine on was whether the surveillance camera caught an act of self-defense, as the defendant was claiming self-defense.

I reviewed the video and counted the shots fired, in what sequence they were fired and from where. I quickly determined the defendant was lying to his attorneys (who knew less than nothing about guns) and told them I couldn’t help them. Because it was a public defender case and I was to be paid by the government, I didn’t even bother to submit a bill. I wanted nothing to do with the case.

Another case (my first one) had to deal with deciding how a teenager had suffered an injury to his hand when handling a J-frame revolver and it discharged, striking and killing his sister. I attempted to recreate the injury using an exemplar revolver, videotaped the test and showed the court how the injury occurred.

The second hurdle to be cleared is that the opinion offered must be the result of generally accepted methods of investigation, which need to be discussed in the expert report.

Straight Facts, No Opinions

What an expert witness cannot do is give an opinion as to the ultimate question. Meaning, was the act an act of justifiable self-defense? When someone says they’ll just hire an expert to give such an opinion and they will walk free, it indicates a naive knowledge of the law. Attorneys are guilty of this naivety at times, as the role of the expert isn’t covered sufficiently in most law school curriculum. I spend a lot of time telling attorneys I cannot give the opinion they seek, but usually the evidence can be explained so the jury understands what the prosecutor is saying isn’t plausible or likely to have occurred, leading to that acquittal.

Occasionally, the expert witness can make such a statement though. For instance, when the prosecutor asks for the expert’s motive for testifying. This usually comes up in pro bono cases (meaning the expert is working for free, which happens occasionally) when the case is so egregious and there’s no money to pay for the expert. Some experts take the case anyway, as I’ve done on occasion.

Typically, the question of how much you’re being paid to testify is asked of the expert, implying the expert will say anything the defense wants him or her to say for the money. When this occurs, it opens the door to the following response: “Well, nothing counselor.” And if the gods are shining upon the expert that day, the attorney will then ask “Why?” The expert’s response usually follows something like this: “I took this case for no fee, because I have never seen such a miscarriage of justice in all the time I have been doing this.”

I have only had it happen to me once in my career, but it was enjoyable to be able to answer the question.

Regular Rarity Of Expert Witnesses

Expert witnessess are likely needed in just about all self-defense cases but, for two reasons, are rarely used.

The first reason is the attorneys handling the case don’t realize they need one, and the second reason is experts typically cost a great deal of money.

The fact of the matter is that many otherwise qualified people simply don’t understand they could become a court-recognized expert and never pursue it. If the industry had an armed citizen who was a recognized expert in all counties in the country, willing to testify for a fellow armed citizen who was being prosecuted for a legitimate act of self-defense, we’d see fewer innocent persons convicted.

Think about becoming one of these experts.

Editor’s Note: This article originally appeared in the April 2022 issue of Gun Digest the Magazine.

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