Vehicular Crime
The Investigators Role In Investigating Criminally
Negligent Homicide and Manslaughter Cases
By Jack Murray CLI, CFE, MBA

Traffic fatalities are always tragic, no matter what the circumstances, but they are a double tragedy when as a result, one of the drivers is faced with criminal charges.

The terminology may vary from state to state, but the basic components are the same. In Texas we have three major charges: Criminally Negligent Homicide, Manslaughter and DUI Manslaughter.

The investigators role changes slightly from one charge to another, but the major components are the same. The defense approach with the first two charges, is that the accident was unavoidable, in the case of a driver being under the influence, you strive to show the accident could have happened whether the driver was intoxicated or not.

In 1998, we had a case of criminally negligent homicide that involved a young man, driving home from work at 2:30 AM, on Interstate 35, in a rainstorm, striking a parked car and killing the driver of that vehicle. According to the police, our client was negligent in not seeing the parked car, was traveling at an excessive rate of speed, not paying attention and thus causing the accident.

On the surface this seemed like a very difficult case to attack. However, after a close examination of all of the circumstances, we learned that the accident occurred on an off ramp, and the car that was struck was sitting there with no lights on, in the exit lane. I was retained as both the investigator and one of two accident reconstructionist involved.

You have to understand the elements of the crime before you start your investigation. Criminally negligent Homicide, in Texas, is defined as:

"a person commits an offense if he causes the death of an individual by criminal negligence."

Criminal Negligence is defined as:

A person acts with criminal negligence, or is criminally negligent, with respect to circumstances surrounding his conduct, or the result of his conduct when he ought to be aware of substantial and unjustified risk that the circumstances exist or the result will occur. The risk must be of such a nature and degree that the failure to perceive it constitutes a gross deviation from the standard of care that the ordinary person would exercise under all the circumstances as viewed from the actor's standpoint."

Our job was to see if the circumstances of the accident fit the requirements of the law for criminally negligent homicide.

The first step, is an in depth interview with your client. Document everything they did for the twenty four hour period before the accident. Everything they ate, drank etc. Be particularly meticulous about how much they ate and drank and how much sleep they had prior to the accident. Fatigue and stress contribute significantly to perception and reaction time.

Check your clients credit cards. If they show very small charges at the last place they visited, good. If there are large charges, find out how many people were involved. These people could become very important witnesses as to the condition of your client prior to leaving that last place.

See how much of a tip the client left. The usual tip is 20%, if it's a large bi
was like pulling teeth, despite the District Attorneys obligation under law to disclose this information, we had to prove to the judge they existed.

A paramedic at the scene, told us that "the police were taking a lot of pictures" and "there was a young guy who stopped before we got there. He was a former medic and gave aid to the injured driver."

After reviewing the photos, we were reasonably sure that the lights of the parked vehicle were not on. A physical examination of the bulbs, at a later date, confirmed this. Trial testimony showed the police never examined the bulbs.

We will never know why the vehicle was parked where it was, But, we believe that the parked cars driver thought he was on the shoulder of the road when he actually was in the exit lane.

We went back to the scene, in a rain storm, at approximately the same time that the original accident happened and found that visibility was a very serious problem. First, there were two different types of street lights at the scene, both cobalt and flourescent. There was additional ambient lighting from a large Western Wear store on one side of the road and a huge used car lot on the other side. All of this created what is commonly referred to as a "wall of light." add to this the falling rain, and depth perception became next to impossible.

We made a video tape, with me sitting in a vehicle exemplar, a 1987 Mercury Topaz, with the lights out, while my associate, Jim Moore, and a cameraman came up from behind me in the rain and taped the parked vehicle. The game plan was for Moore to swerve away from me at the last minute. On paper this sounded quite simple. We had two way radio contact but as Moore approached, a slight glitch happened, a semi rig came up from behind him and negated his ability to swerve. Moore screamed into the two way radio "get out of the way." I floored the parked Topaz, as he hit the brakes on his vehicle. We missed a collision by inches.

When it came time for trial, guess what the State offered into evidence ? A video tape made at two o'clock, on a Sunday afternoon, bright and clear and everything visible. No lights, no rain.
What impression would the jury have had, about our drivers actions, if they had not seen the video made at night in the rain??

The State listed one witness on the accident report. After interviewing him we determined he did not really see the accident, only the after effects. Guess what? When he showed up in court he changed his story and now he was an "eye witness." Our signed, and recorded, statements were used to impeach his testimony. I can't describe the look on his face when I was called to the witness stand to produce those documents. He was sitting in the witness room, and as I passed the door, he looked like he was going to have a stroke. He should have been charged with perjury.

The passerby medic was located by an ad in the newspaper, and he was able to testify to the condition of our client after the accident as being visibly shaken and saying "I never saw the car till I was on top of it." This young man also confirmed that the lights of the parked car were not on at the time of the accident.


The question put to the jury was quite simple; "knowing the true circumstances of this accident and all of the mitigating factors, do you believe that there is reasonable doubt that the charges against the defendant met the criteria of the law for being guilty of criminally negligent homicide?"

The jury brought back a verdict of "not guilty."

The week between Christmas 1997. and New Years of 1998, we got a case where our client, the National Sales Manager for a local company, was leaving a Christmas party at a local restaurant, and made a wrong turn and ended up going the wrong way on a one way street. The street involved was the exit ramp of the Dallas North Tollway. The end result was a head on collision with another vehicle at a combined speed of approximately 100 miles per hour.

Our clients blood alcohol was a .12. In Texas, at that time, a .1 blood alcohol concentration was considered intoxication. (Note: In 1999 it became .08).

Again, we had to consider the requirements for DUI Manslaughter: "The defendant, operated a motor vehicle, in a public place, while intoxicated and by reason of that intoxication, caused the death of another by accident or mistake."

Intoxication means:
A. "not having the normal use of mental faculties, by reason of the introduction of alcohol or any other substance into the body."
B. "Not having the normal use of physical faculties, by reason of the introduction of alcohol or any other substance into the body."
C. "having an alcohol concentration of 0.10 or more"

The attorneys did the ususal arguments against the intoxication portion, chain of custody, validity of tests etc. but the blood test was admitted into evidence. Thus, the State was half way there. Now, our job was to prove that the accident could have happened with, or without, alcohol.

Again, we needed to get all available materials from the State. This was quite helpful because the Dallas Police Department pictures showed the location of the vehicles, at the time of the accident, and clearly showed no "One Way" signs visible, before or after, the point of impact. These pictures also showed that both vehicles had equal opportunity to avoid the accident. An examination of the autopsy report showed that the deceased driver was also intoxicated.

While comparative, or contributory negligence, is not an accepted defense in this type of case, it definitely plays a part in the thinking of the jury.

There was a serious question about the way the streets were marked as far as designating one way traffic. We went to the scene, at approximately the same time of the accident, and shot both still and video photos. In the daytime, we shot overhead stills and obtained aerial views of the scene.
The layout of the streets was such that when you exited the parking lot of the restaurant you could not see any "One Way" signs and if you weren't familiar with the streets it was very confusing, even in the daylight.
Our position was, that this situation was so confusing that any person, drunk, sober or whatever could have made the same mistake that the defendant made.

We also produced several witnesses who testified to the mental and physical condition of the defendant when he left the restaurant. This was to deal with the question of loss of mental or physical faculties. The police officer could not really testify to our clients condition because the client suffered head and facial injuries in the accident.

A toxicologist testified that while the defendants blood alcohol content was legally intoxicated that was not necessarily a foregone conclusion that he suffered impaired physical or mental capacities. The toxicologist drew the comparison of a young high school girl who goes to her senior prom, has one drink and throws up all over her dress and her date. Meanwhile her date, the captain of the football team, has four beers, and is doing just fine.

The States' closing was simply, "we have a legally intoxicated driver and we have a dead body, that's intoxication manslaughter."
Fortunately, the jury understood the premise that the accident could have occurred, without alcohol or drugs being a factor. They found the defendant guilty, but gave him probation.

What's the common thread to all of these investigations? First, understand the elements of the crime. Review every piece of material the State has. Ask a lot of questions, to make sure you have everything they have. Exculpatory evidence is often left out in their disclosure.

Document as carefully as you can, what the scene was like at the time of the accident. Find witnesses to the condition of your client prior to the accident. While you are getting statements be sure and ask if they saw anyone taking still or video pictures. We had a case in Richardson, Texas, where the police took video at the scene, but never disclosed this until after the criminal case was disposed of and my son made a discovery motion with the City Attorney for the civil case involved. Their explanation was, that they didn't consider this exculpatory evidence. Forget that this is more fitting a call for the judge to make.

Nowadays, lots of folks have video cameras in their cars and stop to take shots of a big accident. I currently have a civil tractor trailer accident case, in Arkansas, where a tourist stopped and took video of the actions of the "jaws of life" rescue efforts. This video also showed the exact positions of the vehicles after the accident, before the police arrived and the vehicles were moved.

Talk with your clients insurance company. They have a vested interest in your client not being convicted. Insurance companies get their adjusters and SIU people out to photograph everything, sometimes within hours after the accident, to cover their liability. Subpoena all the insurance companies involved for everything they have!

Inspect and photograph the vehicles involved. Document such things as the condition of the lights at the time of the accident. Were they on or off? If you don't know how to tell, get someone who does!! Show the principal direction of force, look for trace evidence, paint scrapes, tire marks etc. If you get the case soon enough, photograph the scene for the same kind of evidence, like skid marks, yaw marks, etc. Always photograph the scene as soon as possible, lest later construction change the traffic configuration prior to trial.

Get a reconstructionist and a toxicologist involved, to cover those aspects that you do not qualify as an expert to testify in.

Sometimes your investigation will show that negotiating a good plea bargain is in the best interest of the client. Obviously, that is a choice the defendant and the attorney must ultimately make, but you can at least show them what they are faced with if they take the case to trial.

Above all do not accept anything the State offers as "evidence" without checking it out very carefully. My motto is " In God We Trust, all others we investigate."

About the Author: Jack Murray CLI, CFE, MBA is A Regional Director for Region IV of NALI. He lives in Dallas, Texas, where he specializes in accident investigation and reconstruction. Murray has qualified as an expert in civil and criminal cases in State, District and Federal Courts. He is a two time winner of the NALI Editor- Publisher Award. His latest book, "The Accident Investigators Guide to the Courtroom," will be published by the Institute for Police Technology and Management at the University of North Florida, Jacksonville, Florida, in August of 1999. He can be reached at 214-902-9156 or by email at

Mr. Murray is Author Of:

Accident Investigation In The Private Sector Books I And II
Top Flight Training In Accident Investigation Recommened By
The National Association Of Legal Investigators

Marketing And Management Maximizer For
Your Private Investigative Agency

Your Inside Guide To Maximizing Your Agency
For More Cases And More Clients!

Expert's Guide To Successful Legal Testimony
How To Avoid The Sharks And Come Out Smelling Like A Rose

Photographing Vehicles For Litigation
A Step-By-Step Guide For Investigators

Investigative Photography In The Private Sector
Your Guide To Better Investigative Photography