Here is how it routinely unfolds on countless CSI-type television dramas that Americans have loved watching for years.
First, investigators are initially stymied when they come upon a horrific crime scene. Someone has been murdered, and the details of “what happened” are anything but clear to the department’s special crime scene experts.
But not for long, as evidenced by the arrival of a so-called “bloodstain pattern analysis” expert. The spatter of blood left behind in the crime’s wake, while being flatly baffling to the first investigators on the scene, is as clear as a rudimentary finger painting to the BPA technician. What others see as an impossibly complex mess is an easily followed trail of proof for him or her.
The inevitable result: an infallible finger of proof pointing straight at the wrongdoer. Guilt established, case closed.
BPA: not the slam-dunk certainty portrayed on TV
Candidly, bloodstain pattern analysis invites as many questions as it does accolades suggesting its unvarying accuracy at complex crime scenes. Real-world results do indeed feature many correct conclusions, but those outcomes come in tandem with many questionable views and outright mistakes as well.
And when the latter is accepted as truth, innocent persons can suffer egregiously.
So notes a recent in-depth article underscoring accuracy-tied concerns surrounding forensic “science” techniques. Reason Magazine notes that BPA “has come under increased scrutiny over the last decade” for linked “concerns over reliability and a number of wrongful convictions.”
BPA study results: some food for thought
Although commentators on BPA have ready access to myriad research sources gauging bloodstain pattern analysis, nothing has piqued their interest so much as study results just released in the publication Forensic Science International. Researchers in that effort analyzed BPA reliability and accuracy in what has been deemed “the largest-ever black-box study” on its merit in criminal cases.
The result: BPA’s utility can certainly be questioned. In fact, it can reasonably be regarded with suspicion.
Here’s why, note study authors: Results show “that conclusions were often erroneous and often contradicted other analysts.”
There is a caveat tied to the study. Researchers’ probing into analysis and conclusions was limited to controlled blood samples and evidence obtained from real cases. It did not involve BPA linked to actual casework. Study principals say that blood spatter researchers working on real cases might reasonably have a higher accuracy rate, given that they “have additional context from the crime scene.”
The bottom line in either case is that forensic evidence accuracy will always involve an element of subjectivity and the potential for human error. Proven and aggressive defense legal counsel can help safeguard against that.