Case Study: Nighttime Auto-Pedestrian Accident Reconstruction

February 4, 2007

Mr. Jeff Richards
Farmers Insurance Company
Farmers National Document Center
P.O. Box 268994
Oklahoma City, Oklahoma 73126-8994

Re: Claim #: 1004841350-1-1
Insured: Brenda Bullock
Claimant: Tre Strider Tullos
Date of Loss: 1/2/04

Our File # TC-2412

Dear Mr. Richards:


You asked Texas Claims & Consulting Co. to review the material provided and then prepare a preliminary accident reconstruction expert opinion as to how the above styled fatal accident actually occurred.

Additionally, you asked that we discuss any other significant issues that may have contributed to or been the cause of the accident.

Finally, you asked that we prepare a written report of our findings, conclusions and opinions.

This expert report is based on the material provided, our office research, and my training, knowledge and over 33 years experience as an accident investigator and reconstruction expert. It should also be noted that any new information may, or may not, affect my final opinion.


This case was originally assigned to, and accepted by, our office on December 18, 2006.

Material Provided for Review

  • A summary of the DPS trouper meeting
  • The Texas Department of Public Safety Accident Report
  • Autopsy
  • Letters and notes found on the decedent’s body.

Brief Historical Review

This auto/pedestrian, nighttime, fatality accident occurred on January 2, 2004, at about 7:42 P.M., about eight miles north of Wimberley, Texas on Ranch Road # 12 at or near its intersection with Woodcreek Drive.

Sydnee Nicole Bullock was the driver of a 1985 white GMC pickup truck owned by Brenda Bullock Carpenter. Ms. Bullock was proceeding southbound on Ranch Road # 12.

Tre Strider Tullos, the pedestrian, was walking southbound on Ranch Road # 12 when Ms. Bullock struck him.

Significant Police Data

Trouper Brian K. Freeman with the Department of Public Safety investigated the accident. The officer reported the following significant information, in part.

  • The location of the accident
  • The time of the accident was 7:42 PM
  • Nighttime driving conditions
  • The area speed limit was 55 mph
  • There was no roadway construction evident
  • The impact area was dark and unlighted
  • The weather was “clear/cloudy” (Neither specifically designated)
  • The road surface was dry
  • The road surface was blacktop (bituminous concrete)
  • The pedestrian was wearing dark clothing
  • The vehicle did not leave any skid marks, neither on nor off the roadway
  • Mr. Tullos’ wallet contained several hand-written documents

The Medical Examiner’s Report

The medical examiner concluded the cause of death was a broken neck, crushed abdomen and crushed pelvis caused by the auto accident. The drug screen indicated levels of cannabinoid (marijuana) in the body.

Investigating Officer’s Interviews

The investigating officer took written statements from both Ms. Bullock and Ms. Carpenter. In summary, both stated the pedestrian appeared suddenly and the impact could not be avoided. There is an indication the driver noticed a deer on the opposite side of the roadway but this activity would not have any bearing on the basic facts of the case because drivers are supposed to be looking in different directions as they drive.

Description of The Accident Site

The investigating officer took measurements of the accident site at the time of the crash. A review and analysis of those measurements provided ample information to understand the basic roadway design and distances involved.

We used the officer’s hand-written drawing to create our scale diagram (see attached).

At this time a field visit by our staff is not necessary based on the assignment and information to date.

Total Distance To Stop

The total distance to stop from any given speed is a combination of the calculated slide distance and the distance the car traveled during the driver’s reaction time.

The calculated slide distance from any given speed can be determined by using accepted scientific formulae1. In this case the posted speed limit was 55 miles per hour so our calculation is based on that figure.

Given: Initial Velocity of 55 mph = 80.66 fps
Coefficient of Friction = 0.70
Deceleration Rate = -22.54 fps/s
Perception/Reaction Time = 2.5 to 3.5 seconds
Low Beam Headlights = 150 feet of beam distance required by Texas Statutes
Find: Total Distance to Stop


The distance the car traveled during the driver’s perception/reaction time would range from 201 to 282 feet. This is the distance traveled before any braking begins.

The calculated slide distance is 144 feet.

The total distance to stop is between,

Reaction time distance = 201 feet
Slide distance = 144 feet
Total = 345 feet
Reaction time distance = 282 feet
Slide distance = 144 feet
Total = 426 feet

It is important to note that in both of the above calculations the driver’s reaction time distance exceeds the low beam headlight distance of 150 feet. In other words, as the pedestrian comes into view at 150 feet, the vehicle will travel from 201 – 282 feet, before any braking would occur. The impact is within the driver’s reaction time and therefore unavoidable. Slamming on the brakes would not have been a successful avoidance maneuver.

A logical extension of the above analysis is to question whether or not the driver could have swerved and avoided impact. In reality, the reaction time distance would also apply to any “swerve to avoid” maneuver. In other words, any swerve maneuver cannot take place until the end of the perception/reaction time. If the impact occurs during the perception/reaction time, then it follows logically that a swerve avoidance maneuver would also fail.

Finally, we must remember that braking or swerving to avoid are not negligence issues but rather avoidance tactics that, unfortunately in this case, would not have been successful.

Texas Transportation Code 552.006

The Texas Transportation Code provides rules and regulations for pedestrian movement.

Section 552.006 states, in part,

“…if a sidewalk is not provided, a pedestrian walking along and on a highway shall if possible walk on (1) the left side of the roadway; or (2) the shoulder of the highway facing oncoming traffic…”

In this case, Mr. Tullos was walking on the right side of the highway and was, therefore, in violation of this statute. The accident would not have occurred had he been on the correct side of the roadway.

Contributing Factors

Nighttime pedestrian accidents have their own set of contributing factors. They include, but are certainly not limited to,

  • A pedestrian in dark clothing is harder to see due to the low reflectivity of the light reaching the garments.
  • Pedestrian visibility is even more difficult if the area is dark, unlighted and against a dark background; such as roadside trees, shrubs or other dark objects.
  • The human eye simply does not see as well at night as during the daytime.
  • A vehicle’s headlight aim, even one degree off, can reduce visibility distance from 24-45%2
  • The effect of dirt on the windshield or headlights reduces useable light and increases glare.
  • Pedestrian’s frequently draw the conclusion that since they can see the car’s headlights that the driver can see the pedestrian. This assumption is completely incorrect.
  • Drugs and/or alcohol is estimated to be a contributing factor in 40% of auto fatalities, and almost 75% of all fatal crashes involving drugs and/or alcohol occur at night3. In this case Mr. Tullos had drugs in his system.
  • A driver’s “Danger Expectancy” relates to various driving circumstances in which the driver is, or is not, alerted to a dangerous situation. For example, a driver sees a group of children on bikes in the street ahead. The driver’s “Danger Expectancy” is heightened. On the other hand a driver would not expect to see a pedestrian on a dark county road in a rural area.
  • A driver’s field of vision is dramatically reduced as speed increases. At 55-60 mph, a driver’s field of vision is reduced to approximately 1/5 of stationary vision.4

The Suicide Issue

The police documents included several hand written notes signed by Mr. Tullos. The notes possibly suggest a very troubled teenager (he was 15 at the time) in need of professional counseling and guidance. Alternatively, the hand-written notes could be the lyrics to a song he wrote as dated “9/10/94”, entitled “Welcome to My Mind.”

However, the references to death and extermination simply cannot be ignored as whimsical fantasy or song lyrics, because he appears to be writing a projective theme. His use of drugs at the time of the accident may have played a significant role in his mental state

A least one note is dated September 10, 1994. Since the accident occurred on January 2, 2004, it may be difficult, but not impossible, to investigate his background to determine his mental state at the time of the accident.

I would recommend that a psychological autopsy be conducted to either consider or rule out the possibility of suicide as a possible cause for the accident.


It is my expert opinion this accident occurred because Mr. Tullos was walking on the wrong side of the road, wearing dark clothing at night, in the moving lane of traffic. Additionally, his use of drugs may have impaired his judgment to the extent that he did not realize that he was placing himself in danger.

It is also my expert opinion that Ms. Bullock is negligent free based on numerous factors surrounding the incident, including but not limited to, the posted speed, nighttime driving conditions, pedestrian visibility issues, calculated stopping distances, and nighttime perception/reaction time.

1Northwestern University, Basic Motion Equation # 10
2Jerry J. Eubanks, Pedestrian Auto Reconstruction, 1994
3Jerry J. Eubanks, Pedestrian Auto Reconstruction, 1994
4Texas Driver’s Handbook