Accident Investigation Tips (Part 1) - Quickly and Accurately Documenting Evidence

Part 1 begins with a review of terms associated with basic accident/crash investigation procedures. Investigators use two common methods to accurately identify, document, and collect the location of evidence associated with a traffic accident.

The following terms are used in accident investigation: coordinate and triangulation measuring methods, reference point, reference line, right angles, triangles, field sketch, scale drawing, tire marks, final rest, maximum engagement, etc. 

Reference Points are permanent places near an accident scene that investigators use to pinpoint crash scene evidence. In every accident investigation there will be evidence which needs to be identified and collected. Additionally, investigators need to document the location of that evidence in relation to the other evidence. The value of reference points is that they allow for re-location of that evidence on drawings and maps, if needed in criminal and civil court proceedings. 


This photo shows objects that can be used as Reference Points (Yellow marks) along a typical highway. Reference Points (RPs) are places that are used as a permanent place from which evidence can be marked and located. The RPs highlighted here include: lamp posts, building corners, manhole covers, and where roadway edges intersect. These RPs are used because they can be recreated later, should the intersection be reconstructed.

This diagram also displays reference points:


Next Post - Using the Coordinate Measuring Method to locate evidence from these RPs.