What is a common method for estimating vehicle speed prior to a crash?

The analysis of skid marks on the roadway is a common and effective method for estimating vehicle speed prior to a crash. When a vehicle brakes suddenly, the tires leave marks on the roadway that can be analyzed to determine various factors related to the incident, including speed.

Skid marks can provide critical information about how fast a vehicle was traveling before the driver attempted to stop. The length and type of skid marks (such as locked-wheel skids versus threshold braking) can be measured and, when applied to physics formulas, can give an estimation of the speed at the time the driver began braking. This method is particularly useful because it relies on physical evidence that can be quantified and is less subjective than assessments based solely on personal opinions or recollections.

While other methods, such as witness accounts or vehicle damage inspections, can provide useful information during a crash investigation, they are inherently more subjective. Witness accounts can vary greatly and depend on individual perceptions, which may or may not be accurate. Similarly, while vehicle damage can suggest speed, it is often influenced by many factors, such as the angle of impact and the type of vehicles involved, making it less reliable for determining exact speeds compared to skid mark analysis.