Preserving Crash Scene Evidence
Physical evidence at a crash scene can change or disappear quickly after a collision. Skid marks fade, debris is cleared, vehicles are moved and roadway conditions change. Early documentation and preservation of the scene can help ensure that the information needed for a meaningful reconstruction remains available.
Why Scene Evidence Is Time-Sensitive
Roadway evidence such as skid marks, yaw marks, gouge marks and debris patterns can be disturbed or lost within hours or days of a collision. Traffic-control devices may be repaired, and weather and traffic can alter the scene. Once physical evidence is gone, it generally cannot be recreated, which can limit the conclusions a reconstructionist can reach.
What Physical Evidence May Be Relevant
Relevant physical evidence may include skid and yaw marks, gouge and scrape marks, debris patterns, vehicle resting positions, roadway geometry, surface conditions, sight lines and the status and timing of traffic-control devices. The evidence that exists depends on the specific collision and how quickly the scene is documented.
How Scene Preservation Supports Reconstruction
Scene documentation provides the foundation for collision reconstruction. Measurements, physical evidence and visual records from the scene are used in speed analysis, time-and-distance analysis and other reconstruction methods. Accurate, early scene documentation helps ensure that reconstruction is based on the evidence that actually existed at the time of the collision.
Witnesses and Video Are Not Guaranteed
Witness canvassing and video canvassing can identify people and recordings that may have captured the collision, but witnesses and recordings are not always available. People may not have seen the collision, and nearby cameras may not have recorded it or may have overwritten the footage. Canvassing identifies what is available; it cannot create evidence that no longer exists.
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Crash-Scene InvestigationQuestions We Address
Why is early crash scene documentation important?
Physical evidence at a crash scene can change or disappear quickly. Skid marks fade, debris is cleared and vehicles are moved. Documenting the scene as soon as possible helps preserve information that may be important for later analysis or litigation. Once evidence is lost, it often cannot be recovered.
What should be preserved at a crash scene?
Where possible, preserve roadway evidence such as skid and gouge marks, vehicle resting positions, debris patterns, traffic-control device status and any available video. A reconstructionist can advise on what documentation and access will be needed for a meaningful analysis.
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For collision reconstruction assignments, vehicle-data questions, or expert-witness availability, contact our office directly.