MCOLES Crime Scene Investigation Questions and Answers — Questions and Answers
Question 1: An officer is the first to arrive at a homicide scene inside a residence. After confirming the victim is deceased and the scene is safe, what is the officer's most critical next step to prevent evidence contamination?
- Begin interviewing potential witnesses who are on scene.
- Establish a single entry and exit path and document all personnel moving through it. (Correct answer)
- Start collecting fragile evidence, such as fingerprints on a doorknob.
- Immediately begin a detailed search of the entire residence for additional evidence.
Correct answer: Establish a single entry and exit path and document all personnel moving through it.
To maintain the integrity of a crime scene, controlling access is paramount. Establishing a common approach path, or a single point of entry and exit, minimizes unnecessary foot traffic and reduces the risk of contaminating or destroying evidence. Documenting everyone who enters and exits through this path (a scene log) is a standard and critical procedure.
Question 2: Which of the following best describes the primary purpose of maintaining a strict chain of custody for an item of evidence?
- To ensure the evidence is stored in the most secure location possible.
- To provide a chronological paper trail documenting who has handled the evidence, ensuring its integrity and admissibility in court. (Correct answer)
- To quickly determine which officer is responsible for transporting the evidence to the lab.
- To create a record of the evidence's monetary value for insurance and reporting purposes.
Correct answer: To provide a chronological paper trail documenting who has handled the evidence, ensuring its integrity and admissibility in court.
The chain of custody is a formal, written record that tracks evidence from the moment it is collected until it is presented in court. Its fundamental purpose is to prove the evidence is authentic and has not been tampered with, altered, or substituted, which is essential for it to be admissible during legal proceedings.
Question 3: A single officer must conduct an evidence search in a small, square room with a significant piece of evidence located in the center. Which search pattern would be most efficient and logical to use in this situation?
- Line (Strip) search
- Grid search
- Zone search
- Spiral search (Correct answer)
Correct answer: Spiral search
The spiral search pattern is highly effective for a single searcher in a room or defined area. The officer can start at the central piece of evidence and spiral outward, or start at the perimeter and spiral inward. This method ensures thorough coverage without the need for multiple officers that line, grid, or zone searches often require for efficiency.
Question 4: An officer finds a wet, bloody firearm at an outdoor crime scene on a rainy day. What is the proper procedure for packaging this specific piece of evidence?
- Place the firearm in a sealed plastic bag to prevent it from getting wetter.
- Wrap the firearm tightly in a paper bag to begin absorbing the moisture.
- Secure the firearm in a breathable cardboard gun box, allowing it to air dry. (Correct answer)
- Immediately unload the weapon and package the ammunition and firearm separately in plastic bags.
Correct answer: Secure the firearm in a breathable cardboard gun box, allowing it to air dry.
Packaging a wet item, especially metal or an item with biological evidence, in a plastic bag will trap moisture, which can promote rust and the degradation of DNA evidence. The best practice is to package the firearm in a container that allows it to air dry naturally, such as a cardboard gun box. This protects the weapon, preserves trace evidence, and prevents destructive moisture buildup.
Question 5: Which of the following is an essential component that MUST be included on a finished crime scene sketch for it to be considered complete and admissible?
- The brand name of the measuring device used.
- The signature of the lead detective on the case.
- A legend or key to identify the symbols used on the sketch. (Correct answer)
- A list of all officers present at the scene during the sketching.
Correct answer: A legend or key to identify the symbols used on the sketch.
A crime scene sketch uses symbols to represent objects, furniture, and evidence. A legend or key is essential because it explains what each symbol depicts, allowing anyone viewing the sketch (investigators, attorneys, jury) to understand it accurately. Without a legend, the sketch is just a collection of meaningless shapes.
Question 6: Upon arriving at a burglary scene, the first responding officer's primary responsibility, after ensuring the location is safe and addressing any immediate medical needs, is to:
- Conduct a detailed canvass of the neighborhood for witnesses.
- Secure the scene and protect it from contamination or unauthorized entry. (Correct answer)
- Begin collecting and packaging obvious items of evidence.
- Interview the victim in detail about the missing property.
Correct answer: Secure the scene and protect it from contamination or unauthorized entry.
The foremost duty of the first responding officer at any crime scene is to secure it. This involves establishing a perimeter and controlling access to prevent the destruction, alteration, or contamination of physical evidence before it can be properly documented and collected by investigators. All other actions, such as interviewing and collecting evidence, follow after the scene is properly secured.
MCOLES Crime Scene Investigation Questions and Answers
An officer is the first to arrive at a homicide scene inside a residence.
After confirming the victim is deceased and the scene is safe, what is the officer's most critical next step to prevent evidence contamination?