Expert Witness Testimony

Yeah right, you're a what?

When all of the examinations in a particular case are complete the firearms examiner will issue a report of their findings to the submitting party. Although the examinations are complete the case is still only partially finished. The next big step is to present the findings of his or her examinations in a court of law.

Expert testimony is commonplace in almost every criminal trial. Expert testimony is defined in Microsoft's Encarta 97 as...

Expert testimony is that given by a specialist who has been recognized by the court as having expert knowledge about evidence in the case."

Encarta goes on to say..

"Such testimony is governed by different rules than the testimony of ordinary witnesses in a trial. Ordinary testimony is restricted to statements concerning what the witness actually saw or heard. An ordinary witness is prohibited from stating opinions about the case and from quoting statements made by other people. In contrast, an expert witness is allowed to express an opinion about the validity of the evidence in a case and may quote the statements of other experts in support of an opinion."


Do you swear to tell the truth and nothing but the truth, so help you God?

The first step in testifying usually involves stating your name, job description, and where you are employed. I normally explain to the jury what firearms identification is and will tell them a little about our lab system. Next, I will attempt to be recognized or qualified as an expert by the court. I will describe to the jury my education, training and experience.

I will first tell the jury where and when I graduated from college and what degrees I received. Next I will describe in detail the training I received and what schools and other classes I may have completed since starting my career in Firearms Identification. Lastly, I am usually asked how long I have been employed in my present capacity, how many times I have been qualified as an expert in firearms identification and where I have been so qualified.

The judge is then asked, either by the prosecutor or defense attorney, to rule on whether he thinks my qualifications are sufficient for me to be recognized as an expert. The judge will make a ruling and advise the jury that I am to be recognized as an expert in Firearms Identification and can give my opinion as to the findings of my examinations.


Just tell me the facts, ma'am...

At this point I am asked to describe the exhibits that I received, what was requested of me by the submitting officer, what examinations I conducted, what were my findings; and how did I arrive at those conclusions.

It usually goes something like this:

Q. What items did you receive in this case?

A. (Somewhat abbreviated)

I received four exhibits from Det. Smith. Exhibit 1 is a Smith & Wesson 38 Special, double-action revolver, serial number 123456; Exhibit 2 is a fired, plain lead bullet; Exhibit 3 is a spent centerfire cartridge case; and Exhibit 4 is a blue T-shirt.

Q. What were you asked to do with these items?

A. (Somewhat abbreviated)

I was asked to examine Exhibit 1 and determine if it functioned properly. I was asked to determine if Exhibits 2 and 3 were fired from/by Exhibit 1. Lastly, I was asked to examine Exhibit 4 for bullet holes and try to determine how far Exhibit 1 was from Exhibit 4 when it was fired.

Q. What were your conclusions and how did you arrive at those findings?

A. (Very abbreviated)

I determined that Exhibit 1 was a functional firearm (I will also at this point describe to the jury how the firearm operates); that Exhibits 2 and 3 were identified as having been fired from/by Exhibit 1; and Exhibit 4 had a large bullet entrance hole in the front chest area and gunshot residues were found around this hole that indicate Exhibit 1 was in close proximity to Exhibit 4 when fired.

I would then explain to the jury how I arrived at these conclusions by describing the principles of Firearms Identification detailed on the various pages of this web site (Firearms Identification, Firearm Function Testing, and Distance Determinations).

You work for who?

Firearms Identification is a branch of Forensic Science and as such those who qualify are scientists. It is often assumed that since I work for a law enforcement agency that I have a vested interest to help the law enforcement community prove the facts of a case and help gain a conviction through my testimony. Actually, the job that the firearm examiner performs is not to prove innocence or guilt. As a scientist our job is to merely convey to the jury what we did, how we did it, and what our results were. It is up to the jury to decide innocence or guilt through the process of hearing all of the facts of the case. The jury will hear my testimony and decide if it is or is not relevant to the case.

As scientists and expert witnesses (and to remain as such) it is of the utmost importance that we maintain complete impartiality in our job. I would take great offense to someone implying I am testifying for or against anyone. I am simply conveying facts based on a degree of scientific certainty, nothing more.

When testifying in court it is the responsibility of any expert to treat the prosecutor and defense attorney with an equal degree of candor. The jury will see how a witness reacts to questions and will use those reactions to judge, for themselves, whether you are telling the truth or are stretching the truth to one side's benefit.

All of the examinations one may conduct will be for nothing if the expert cannot convey the examinations conducted in a way that the jury can understand and believe.


Home | Top