CFL Crime Scene Investigation Procedures

Question 1

What is the first priority for a CFL arriving at a crime scene involving a lock or door?

Accepted Answer

Documenting the scene before touching any evidence

Answer

Immediately picking the lock to assess its operational condition

Answer

Removing the lock for transport to a laboratory

Answer

Interviewing the property owner about missing or duplicated keys

Question 2

Why should a CFL avoid using WD-40 or lubricants on a suspect lock cylinder at a crime scene?

Accepted Answer

Lubricants can obscure or destroy trace evidence such as metal fragments, pick marks, and debris

Answer

WD-40 will cause the cylinder plug to seize permanently inside the housing

Answer

Using lubricants violates ALOA professional standards for forensic examiners

Answer

Lubricants create a fire hazard when used in indoor crime scene environments

Question 3

What information should be recorded in a CFL's scene notes before removing a lock for laboratory examination?

Accepted Answer

Location, orientation, door type, lock brand and model, and photographic reference numbers

Answer

Only the property owner's name and insurance policy number

Answer

The suspected perpetrator's identity and motive if already known

Answer

The responding police officer's badge number and arrival time only

Question 4

When photographing a lock at a crime scene, which lighting technique best reveals pick marks and tool marks?

Accepted Answer

Oblique (raking) lighting from a low angle to the lock surface

Answer

Direct overhead flash for maximum uniform brightness

Answer

Natural diffuse sunlight through nearby windows

Answer

Ultraviolet light used exclusively without visible spectrum illumination

Question 5

What is the correct method for packaging a lock removed from a crime scene for laboratory transport?

Accepted Answer

Rigid container with padding, properly labeled with case number and chain of custody documentation

Answer

Standard plastic zip-lock bag with the collecting officer's initials written on the outside

Answer

Wrapped in newspaper and loosely placed inside a cardboard box

Answer

Taped directly to the evidence submission form for compact transport

Question 6

A CFL is called to examine a door with no signs of forced entry but reports of unauthorized access. What should be the first examination step?

Accepted Answer

Examine the lock cylinder face and keyway under magnification for pick, bump, or bypass tool marks

Answer

Assume the property owner provided a key to the suspect and close the investigation

Answer

Immediately disassemble the lock to check and measure individual pin heights

Answer

Contact the lock manufacturer to inquire whether any keys have been reported stolen