CSI - Crime Scene Investigator Impression and Pattern Evidence Questions and Answers

Question 1

An investigator discovers a faint, two-dimensional dusty footwear impression on a dark-colored tile floor. Which of the following collection methods would be most effective for recovering this type of evidence?

Accepted Answer

Electrostatic dust print lifter

Answer

An electrostatic dust print lifter is the most effective method for collecting dry or dusty residue impressions. It uses an electric charge to attract and bond the dust particles to a special lifting film, preserving the delicate details of the impression with minimal disturbance.

Question 2

A three-dimensional footwear impression is found in mud at an outdoor crime scene. Before casting with dental stone, what is a critical first step in the documentation process?

Accepted Answer

Taking examination-quality photographs at a 90-degree angle with a scale.

Answer

Properly photographing impression evidence before any other collection technique is applied is a critical step. Examination-quality photographs must be taken with the camera positioned directly above (90 degrees) and parallel to the impression, including a scale, to accurately capture its size and details for later comparison.

Question 3

A forensic examiner is comparing a tool mark from a crime scene with a suspect's pry bar. The examiner notes that both the questioned mark and the test mark were made by a tool with a 1-inch flat tip. This observation relates to what type of characteristic?

Accepted Answer

Class characteristics

Answer

Class characteristics are measurable features or traits of a tool that are predetermined by the manufacturer's design, such as the width of a screwdriver tip or the shape of a pry bar. These features can associate a tool mark with a group of similar tools but are not unique.

Question 4

At a homicide scene, a bloody footwear impression is discovered on a light-colored linoleum floor. The impression is visible but faint. Which chemical enhancement technique is most appropriate for improving the detail of this bloody pattern for photography?

Accepted Answer

Amido Black

Answer

Amido Black is a protein stain that reacts with proteins found in blood, staining them a dark blue-black. This enhances the contrast of visible or latent blood impressions on non-porous surfaces, making it ideal for photographing faint bloody footwear patterns. Luminol is used for detecting latent blood, not for enhancing detailed patterns.

Question 5

Which of the following describes a 'plastic' impression?

Accepted Answer

A tire track left in soft soil or snow.

Answer

A plastic print is a three-dimensional impression left on a soft, malleable surface. Examples include shoe or tire tracks left in sand, mud, or snow, where the object has physically indented the surface.

(CSI) Crime Scene Investigator Practice Test

(CSI) Crime Scene Investigator Practice Test

CSI - Crime Scene Investigator Impression and Pattern Evidence Questions and Answers