Evidence Documentation & Interpretation Flashcards

When preparing a scaled diagram of a crash scene, what is the minimum recommended scale for a diagram submitted in a legal proceeding?

Answer: A scale that clearly shows all relevant evidence with legible dimensions

The scale should be chosen so that all relevant evidence is clearly visible and dimensions are legible; there is no single mandatory scale, but clarity and accuracy are paramount.

Striations (fine parallel lines) found within a tire skid mark are produced by:

Answer: Individual tread elements (ribs or blocks) of the tire contacting the pavement

The fine parallel striations within a skid mark are created by individual tread ribs or blocks scraping against the pavement surface during the skid.

An accelerometer sled test is conducted at a crash scene primarily to determine:

Answer: The roadway surface's coefficient of friction (drag factor)

An accelerometer sled test measures the deceleration of a known weight dragged across the pavement, allowing calculation of the surface's drag factor (coefficient of friction).

Which photographic documentation technique is specifically used to capture the overall scene context and orient the viewer to the crash environment?

Answer: Overall (overview) photography from a distance

Overall or overview photographs are taken from a distance to establish scene context, show the road environment, and orient the viewer before close-up detail is shown.

In evidence interpretation, 'contact damage' on a vehicle is distinguished from 'induced damage' in that:

Answer: Contact damage is caused directly by the collision force; induced damage results from structural stress transferred through the vehicle

Contact damage occurs at the direct point of impact, while induced damage propagates through the vehicle's structure as a result of those impact forces being transferred.

When documenting night visibility conditions relevant to a crash, which measurement is most important to record?

Answer: The illumination levels (measured in lux) at key scene locations

Measuring illumination levels in lux at key scene locations (pedestrian position, driver's view point) provides objective, quantifiable data about visibility conditions at the time of the crash.

When a crash scene contains evidence of multiple impacts or complex vehicle interactions, the reconstructionist should document the scene in what order?

Answer: From the point of first contact forward through the event sequence

Documentation should follow the crash sequence from first contact forward, as this logical order helps establish causation and sequence of events in the reconstruction.