Law Enforcement Criminal Investigation Fundamentals 4

Question 1

DNA evidence at a scene is most reliably collected from a touched surface using:

Accepted Answer

A sterile swab moistened with distilled water

Answer

Touch DNA is recovered by swabbing surfaces with a sterile, lightly moistened swab to lift shed cells.

Question 2

What is the primary purpose of AFIS in a criminal investigation?

Accepted Answer

Searching and matching fingerprints against a database

Answer

The Automated Fingerprint Identification System compares latent or known prints against large fingerprint databases.

Question 3

Latent fingerprints on a non-porous surface like glass are commonly developed using:

Accepted Answer

Fingerprint powder or cyanoacrylate (superglue) fuming

Answer

Powder and superglue fuming are standard methods for visualizing latent prints on smooth, non-porous surfaces.

Question 4

Luminol is used at a crime scene primarily to detect:

Accepted Answer

Trace amounts of blood that may have been cleaned up

Answer

Luminol chemiluminesces in the presence of the iron in hemoglobin, revealing latent or cleaned bloodstains.

Question 5

Why must biological evidence such as bloodstained clothing be packaged in paper rather than sealed plastic?

Accepted Answer

Plastic traps moisture and promotes mold and DNA degradation

Answer

Plastic retains moisture that fosters bacterial growth and degrades biological samples, so breathable paper is used.

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