What should be used as reference points when recording measurements at a crime scene?

Using permanent reference points when recording measurements at a crime scene is essential for several reasons. Permanent reference points are stable, unchanging markers that provide a consistent basis for measurements and documentation over time. These points ensure that anyone revisiting the scene can locate the same positions accurately, allowing for reliable comparisons in future investigations or court proceedings.

While temporary markers may serve a purpose during the initial investigation stages, they do not provide the lasting reliability needed for future reference. Movable objects can easily change location or could be disturbed by investigators or the environment, leading to inaccuracies in measurements. GPS coordinates can offer additional information about the location of the crime scene, but they may not account for specific distances or relationships between evidence items in close proximity to one another. Therefore, relying on permanent reference points is the best practice for establishing a clear and precise layout of the crime scene.