DPS NEWS

Bloodstain Pattern Analysis Service Now Offered by the Crime Lab

The Bureau of Forensic Services (State Crime Lab) has recently added a new forensic testing service for law enforcement, Bloodstain Pattern Analysis (BPA) . Bloodstain pattern analysis involves the interpretation of bloodstains at known or suspected violent crime scenes with the goal of helping investigators draw conclusions about the nature, timing and other details of the crime.

Effective immediately, the Crime Lab will be accepting cases in all areas of Bloodstain Pattern Analysis, including Collection/Documentation, Area of Origin Determination, and Bloodstain Pattern Determination.

From what may appear to be a random distribution of bloodstains at a crime scene, analysts can categorize the stains by gathering information from spatter patterns, transfers, voids and other marks that assist investigators in recreating the sequence of events that occurred after bloodshed.

BPA uses principles of biology (behavior of blood), physics (cohesion, capillary action and velocity) and mathematics (geometry, distance, and angle) to assist investigators in answering questions such as:

• Where did the blood come from?
• What caused the wounds?
• From what direction was the victim wounded?
• How were the victim(s) and perpetrator(s) positioned?
• What movements were made after the bloodshed?
• How many potential perpetrators were present?
• Does the bloodstain evidence support or refute witness statements?