What is the purpose of establishing a perimeter around a crime scene?

• A. To prevent contamination and protect safety of public and responders.
• B. To maximize the number of people inside the scene for interviews.
• C. To allow unrestricted access to all evidence by the public.
• D. To simplify the incident command structure.

Answer: (A)

Restricting access by establishing a perimeter around a crime scene is about preserving evidence and protecting people. Keeping unauthorized individuals out prevents contamination and disturbance of evidence such as footprints, fibers, and DNA, and it reduces safety risks to bystanders and responders. Inside the perimeter, investigators can document and collect evidence under proper chain-of-custody procedures, while the outer area handles crowd control, media, and support personnel to avoid interference with the investigation. The other options would invite disturbance, expose evidence to the public, or complicate management and access.