The potential for severe injury or death to a pedestrian or bicyclist in a collision with a motor vehicle is high for obvious reasons, yet there is often a limited amount of evidence available, which makes these types of crashes challenging for the reconstructionist. One of the primary goals of a reconstruction is to determine the movements of the pedestrian or bicyclist and the motor vehicle before, during and after collision. The reconstructionist uses
- scene evidence,
- rest positions,
- vehicular damage, and
- pedestrian or bicyclist’s injury locations
to determine the speed of the vehicle as well as the relative position of the vehicle and pedestrian or bicyclist at impact. However, there is more to consider.
Visibility and conspicuity are factors in this type of reconstruction. It is important to determine how far in advance a motorist could have reasonably identified a pedestrian or a bicyclist as a hazard and if there were any extenuating circumstances. Poor environmental lighting due to burned out lamps or substandard luminaires can be a factor. Dark colored clothing on a pedestrian or bicyclist reduces conspicuity and lowers contrast with nighttime surroundings. Poorly aimed, dirty or inoperable headlights can reduce the motorist’s ability to see at night.
It is difficult for pedestrians, especially children and the elderly, to judge the approaching speed of a vehicle. Darkness makes it even more difficult for them. It is also important to look at whether the traffic light timing had a role in the collision.
Once the reconstructionist has determined the area of impact and impact speed, it is possible to determine the locations of the motor vehicle and the pedestrian or bicyclist at various points in time. By combining that information with a consideration of the visibility, conspicuity and human factors involved, it can be determined if either party had time to recognize the hazard and take avoidance maneuvers to prevent the collision.