Should Bloodstain-Pattern Analysis Be Filed Under Junk Science?

Watch nearly any forensic crime show on television these days (fiction or fact-based) and you’ll likely hear about the use of bloodstain-pattern analysis (BPA) in the conviction of serious crimes, including homicide. Specifically, bloodstain-pattern analysis refers to the scientific study of bloodstains and their patterns in an effort to determine details about a crime. For example, in one of the earliest known uses of BPA in court, a man’s 1954 murder conviction was overturned when blood spatter patterns found on the man’s pant leg were not consistent with the original notion that he had committed the murder.

Ever since BPA was used to overturn this conviction in the mid-1950s, it has more or less been seen as an accepted form of evidence in court. In recent years, however, the scientific accuracy of bloodstain-pattern analysis has been called into question—and many are calling for it to be reconsidered as a reliable source of evidence in court.

What’s So Questionable About BPA, Anyway?

There are many reasons why the accuracy and reliability of BPA findings have been called into question in recent years, but one of the most common arguments held against this method is the enormous impact the surface on which blood lands can have on the scientific interpretation of a splatter.

Consider, for example, that the exact same blood spatter trajectory would appear very differently when it hits an absorbent material (such as a bedsheet) as opposed to a non-absorbent material (such as a solid wall). It has been found that when blood spatters on absorbent materials, the patterns can appear distorted and lead forensic scientists and investigators to misinterpret the direction from which the blood traveled.

Another issue that many legal professionals have with bloodstain-pattern analysis is that there is currently no nationwide accreditation or certification required for a person to become a BPA “expert.” Unfortunately, as has been seen time and time again in court, many people have been falsely convicted of crimes due to flawed BPA research and findings.

It is also worth noting that in 2009, a National Academy of Sciences study found that “the opinions of bloodstain-pattern analysts are more subjective than scientific,” which promptly called the entire practice into question. More recently, in 2018, the Texas Forensic Science Commission held its own hearing in an effort to implement accreditation requirements for BPA experts in the state of Texas.

The Future of Bloodstain-Pattern Analysis

Only time will tell what the future holds for the admission of BPA “evidence” in state and Federal courts, but it is likely just a matter of time before major changes are made to the way this evidence is admitted and weighed in the conviction of serious crimes. While there are certainly some benefits to utilizing BPA under certain circumstances, the United States court system would likely benefit from having stricter requirements. Individual states may also need to consider implementing certification or accreditation requirements for forensic scientists who wish to represent themselves as BPA experts.

Are You Facing a Criminal Conviction?

If you’re currently facing a criminal conviction, regardless of whether your case involves the use of BPA, you need a legal team to represent you and defend your rights in court. The Law Office of Michael D. Litman is here to help. Request your free case consultation today by giving our office a call directly at (914) 268-6855 or filling out our online request form. We look forward to assisting you.