You’re sitting on the couch watching a CSI crime drama and note that it’s just about 7:50 p.m. The show is close to concluding, with no real promise that the guy who you can see is clearly guilty of a heinous crime will be identified and held accountable.
Wait a second. A cop has just walked into the forensics lab with a single piece of hair. A focused lab professional places it under a microscope. Is there still time to catch the bad guy?
Readers know the answer to that. Viewers of such shows almost have an internally ticking click and linked knowledge concerning the outcome in such matters. The public has been broadly instructed time and again that forensic evidence routinely enters the criminal law realm in a conclusive and done-deal manner – it is always correct.
That assumption is noted legions of times, including in one Colorado legal source duly stressing that such evidence is routinely portrayed “as unimpeachable and always reliable in real life.”
Here’s the point, though: Real life erects higher proof thresholds than does the fictional realm. It is actually the case, as that above-cited source notes, that the forensic evidence sphere is far from being error-free. A review of hair-comparison evidence conducted by the FBI stunningly revealed that its reliability was overstated in court as much as 95% of the time.
The implications of that for wrongly convicted individuals – especially in death penalty cases, but also in matters ranging from alleged drunk driving to a variety of other offenses – are both stunning and sad
The broad applicability and reach of forensic evidence
Back to that aforementioned television crime drama. Readers know that the evidence examined by white-coat teams of presumed experts goes far beyond mere hair analysis. Court-offered evidence also features tests and examinations relevant to the following:
- Bite marks
- Voice comparison
- Shoe prints
- Blood analysis using DNA
The American Chemical Society’s take on forensic evidence
What the ACS has to say about forensic evidence used in criminal cases is instructive and arguably weighty far beyond what many other groups contend. Reportedly, the organization is the world’s largest and most-respected scientific society.
It stresses this: All forensic “proof” is circumstantial. It “requires interpretation, and its presence does not necessarily imply guilt.” Forensic evidence “may form part of a case, but it is not the whole case.”
That is flatly logical, no? And it ultimately implies that the real test concerning forensic evidence must focus on human assumptions and evaluation more than on raw data.