Bloodstain Patterns

When violent crimes are committed, it is not unusual for the participants to be injured. If these injuries are accompanied by blood flow, distinctive bloodstain patterns may result that can be used to provide investigative information about the activities which occurred during the commission of the crime.

Blood behaves not unlike those spilled water droplets, and the speed at which the droplets travel when they strike a surface, known to analysts as a target, affects their shape.

Bloodstain pattern recognition can be an important tool to aid in an investigation. The examination of bloodstain patterns is based on principles studied in fluid mechanics, biology, and trigonometry.

The television character Dexter Morgan has mesmerized millions of viewers. Though his vigilante activities are questionable to say the least, the title character of the popular show "Dexter" has captivated the imaginations of a new generation of people interested in a criminology career, especially as a bloodstain analyst, also known as a blood spatter expert.

To understand how analysts interpret bloodstains, one must first understand the basic properties of blood. Blood contains both liquid (plasma and serum) and solids (red blood cells, white blood cells, platelets and proteins).

Learn the history and details of conducting blood spatter analysis at the scene of a violent crime.

Bloodstain Pattern Analysis: is the examination of the shapes, locations, and distribution of patterns of bloodstains, in order to provide an interpretation of the physical events that gave rise to their origin.

Often found at the scenes of violent crimes, the analysis of bloodstains can provide vital clues as to the occurrence of events. Though bloodstain pattern analysis (BPA) can be a subjective area of study at times and often reliant on the experience of the investigator, the idea that blood will obey certain laws of physics enables the examination of blood at an incident scene and on items of evidence to offer at least an insight into what was likely to have occurred.

Qualifications, requirements and application procedures for certification are subject to revision by the Board. The latest official version is always available from the Secretary of the Bloodstain Pattern Analysis Certification Board.

The recognition and analysis of bloodstain patterns can yield useful investigative information. The general role of the Bloodstain Pattern Analyst in a criminal investigation is to assist in the reconstruction of those events of an alleged incident that could have created the stains and stain patterns present at a crime scene, on items of physical evidence recovered from that scene and on items of clothing that were present at the crime scene.

The IABPA is an organization of forensic experts specializing in the field of bloodstain pattern analysis. The purpose of this page is to introduce you to the IABPA and inform you about our association.

Bloodstain pattern analysis is one method crime-scene investigators use to get the scene to tell a story. Learn about bloodstain pattern analysis and why it works.

The examination of the shapes, locations and distribution patterns of bloodstains in order to provide an interpretation of the physical events by which they were created that is based on the premise that all bloodstains and bloodstain patterns are characteristic of the forces that have created them.

Bloodstains range in both amount of blood and type of pattern - from pools of blood around a body to obvious spatter patterns on the walls to microscopic drops on a suspect's clothing. The shape of the bloodstain pattern will depend greatly on the force used to propel the blood as well as the surface it lands on.

Bloodstain pattern analysis (BPA), one of several specialties in the field of forensic science, involves the study and analysis of bloodstains at a known or suspected violent crime scene with the goal of to helping investigators draw conclusions about the nature, timing and other details of the crime.