What does bloodstain pattern analysis (BPA) do?

• A. Seeks to define the facts surrounding some incident in question.
• B. Predicts the perpetrator's identity.
• C. Measures chemical concentrations.
• D. Determines the time of day.

Answer: (A)

Bloodstain pattern analysis focuses on interpreting the patterns of blood at a crime scene to define the facts of what happened. By examining stain shape, size, distribution, and the directions and velocities that produced them, analysts infer how blood was shed, where people stood, and how events unfolded in sequence. This helps build a factual narrative about the incident and supports statements or timelines with physical evidence, rather than identifying a suspect or measuring unrelated substances.

It does not determine who committed the crime, nor does it measure chemical concentrations, and it does not pinpoint the exact time of day. Those aspects rely on other forensic disciplines and contextual evidence.