Crime Scene Investigation Flashcards

An officer is the first to arrive at a residential burglary scene. After confirming no suspects are present and no medical attention is needed, what is the officer's most immediate priority?

Answer: Secure the scene by establishing a perimeter and controlling access.

The first and most critical responsibility of the initial responding officer, after ensuring the scene is safe, is to secure the area to prevent the contamination or destruction of potential evidence. [6, 7] All other actions, such as interviewing and evidence collection, follow after the scene's integrity has been established.

Which of the following best describes the primary purpose of maintaining a crime scene log?

Answer: To document every individual who enters and exits the secured crime scene.

A crime scene log is a dedicated record used to track every person who enters and leaves the cordoned-off area. [1, 18] This is crucial for maintaining the integrity of the scene and preserving the chain of custody for any evidence found within it. [17]

When handling a firearm discovered at a crime scene, which of the following is the most appropriate initial action for an officer to take to preserve evidence?

Answer: Use gloves and pick up the weapon by the textured surfaces, such as the checkered grip or slide serrations.

To preserve potential fingerprints and DNA, a firearm should be handled minimally, with gloves, on textured surfaces where prints are less likely to be viable. [19] Placing objects in the barrel can destroy ballistic evidence, and sealing a weapon in plastic can trap moisture, which degrades DNA and can cause rust. [20]

While securing an outdoor assault scene, an officer notices a distinct footwear impression in a patch of dirt. Dark clouds are gathering, and it looks like it is about to rain. What is the officer's best course of action?

Answer: Find a cardboard box or other object to cover the impression and protect it from the elements.

The most urgent priority when fragile evidence is threatened by environmental conditions is to preserve it. [27, 28] Covering the impression protects it from being destroyed by the rain. [29] While photography is important, protecting the evidence itself comes first, and casting is a specialized task that should be done after the evidence is shielded.

The concept of "chain of custody" is fundamental to evidence handling. What is its primary purpose?

Answer: To create a chronological paper trail of every person who has handled a piece of evidence.

The chain of custody is a formal record that shows the chronological sequence of every person who has had custody of a piece of evidence from the moment of its collection to its presentation in court. [2, 12] This process ensures the integrity of the evidence by demonstrating that it has not been tampered with, altered, or substituted. [9, 11]

Which of the following is the primary investigative reason for immediately separating witnesses at a crime scene?

Answer: To prevent them from contaminating each other's recollection of the events.

Separating witnesses is crucial to prevent them from discussing the incident among themselves. [4] This ensures that their statements are based on their own individual memories and perceptions, not influenced or altered by what they hear from others, a phenomenon known as memory conformity. [3, 8]