What Is Bloodstain Pattern Analysis? 

A Retrospective Introduction

Modern policing can be analyzed as a profession that works in the present, progresses toward the future, but constantly looks back at the past. Looks into the past?! I know exactly what you are thinking. But, no, we aren’t talking about that old dude with the gray mustache that keeps talking about “the good ‘ole days”. 

With that guy, you have a choice, listen intently and then eventually get yourself into trouble. Or shake your head, wave dismissively and remind him all those things were illegal to do back then too, then go take a class with us to make you the best cop for any call. 

I’ve gone on a tangent, but I digress. 

Law enforcement is asked to investigate the past on every call. Think about it, when you walk up to your victim, suspect, or witness do you ask, “what’s about to happen?”  Nope. You always ask them, “What happened here?” You are looking into the past, reconstructing the situation in your head, and making the best possible decision with the information you have available to you. 

Bloodstain Pattern Analysis: Background

Bloodstain pattern analysis is the same, except there is a healthy dose of science involved. Physics, trigonometry, forensic reports, pathology, chemistry, anatomy, and even principles used in geology we take for granite are used in bloodstain pattern analysis. 

Bloodstain pattern analysis is a method of forensic science that utilizes predictable reactions of blood to various forces to reconstruct actions that took place before you were there.

Blood is unique in that it can be affected by gravity, inertia, and air pressure, which means that the location and shape of blood droplets can provide clues about the sequence of events that occurred. Bloodstain pattern analysts use this information to piece together what happened at the scene, often helping to identify the perpetrator.

A bloodstain pattern analyst can reconstruct crimes by analyzing the patterns, location, interactions, and forensic science reports (DNA, serology, pathology, autopsy, etc) of blood on the scene. They can often determine where victims and perpetrators were potentially standing, who may have been involved, and what type of weapon was used. 

Bloodletting events, such as a stabbing or shooting, can leave unique patterns that can help investigators identify the sequence of events that occurred. Also, equally important in analyzing scenes is the BPA can provide valuable insight into what was not possible at a scene. 

There is a perception, often in defense work, that bloodstain pattern analysis is a “junk science” because it is not based on the scientific method and “is rife with uncertainty.”  

This is simply not the truth. 

Blinded Me with Science!

The scientific method is a process of inquiry that scientists use to explore natural phenomena. It involves making observations, formulating hypotheses, and testing those hypotheses through experimentation. 

Scientific research utilizing proper design, experimentation, peer review and publication in scientific journals is the standard for appropriately trained blood pattern analysts. 

The bloodstain analysts at RTI have undergone the rigorous training program suggested by the National Institute of Technology’s Organization of Scientific Area Committees standard for becoming an analyst. This includes hundreds of hours of training, novel (never before done) research, publication in a peer reviewed journal, presentation at a nationally accepted conference, and successfully passing a certification exam. 

Bloodstain pattern analysis is a valuable tool for any bloody crime scene (deaths, aggravated persons crimes, domestic battery, assault/battery, etc) and Revelations Training and Investigations can help you solve your crimes. 

If you have a case that you would like reviewed, contact us. Our analysts have the training, experience, and courtroom qualifications to provide clarity to your case. Contact us if you would like to discuss a case or even just this topic more!