CFC Bloodstain Pattern Analysis 5

Question 1

Presumptive testing for blood at a crime scene using luminol is most limited by which factor?

Accepted Answer

It can produce false positives with certain chemicals such as bleach or plant peroxidases

Answer

Luminol is a presumptive test that can produce false positives with oxidizing agents like bleach, copper compounds, and plant peroxidases, requiring confirmatory testing.

Question 2

Which scenario would most likely produce a 'projected spatter' pattern rather than impact spatter?

Accepted Answer

Blood spurting from a severed artery under cardiac pressure

Answer

Projected spatter results from blood being propelled under internal pressure (e.g., arterial pressure from the heart), not from an external force striking a blood source.

Question 3

A forensic consultant interpreting a bloodstain pattern should give most weight to:

Accepted Answer

The totality of physical evidence and scene context

Answer

Sound BPA interpretation requires integrating all physical evidence and scene context rather than conforming to a predetermined theory or relying solely on one category of evidence.

Question 4

In a scene where blood is found on both the ceiling and floor, but not on nearby walls, the analyst should consider:

Accepted Answer

Arterial gushing directed upward followed by pooling

Answer

Blood on the ceiling and floor without wall staining could suggest upward arterial spurting that reached the ceiling, with gravity returning blood to the floor, though other hypotheses should be evaluated.

Question 5

When calculating the angle of impact of a bloodstain, the analyst uses the formula arcsin(width/length). If the width is 8mm and the length is 16mm, the impact angle is approximately:

Accepted Answer

30 degrees

Answer

Arcsin(8/16) = arcsin(0.5) = 30 degrees, meaning the droplet struck the surface at approximately 30 degrees from the surface plane.

(CFC) Certified Forensic Consultant Practice Test

(CFC) Certified Forensic Consultant Practice Test

CFC Bloodstain Pattern Analysis 5