If you haven’t kept up with the world of forensic investigations and how they relate to criminal trials, it may surprise you to learn that some of the most familiar forms of evidence seen in courtrooms of yesteryear are now largely considered “junk science.”
All kinds of evidence that were once considered irrefutable and virtually infallible have now been either discredited by the scientific community and some courts, including things like matching the cases of bullets to the grooves and scratches in guns, bit marks on human skin, blood spatter analysis and tire track impressions. Even fingerprint-matching techniques have been heavily drawn into question.
The problem may not totally be with the science or the evidence, but the ability of forensic examiners to accurately interpret what they’re seeing – because things aren’t always as simple as shows like “C.S.I.” or “Forensic Files” would make them seem
Will trace DNA analysis be the next category of junk science to fall?
Consider the issue of DNA analysis. Once upon a time, courts and juries were pretty distrustful of the ability of lab technicians to tie genetic material such as blood, semen, hair follicles and saliva to a specific suspect or defendant. However, as the science behind DNA testing evolved and judges and juries grew more familiar with the idea, DNA slowly evolved into an evidentiary “gold standard” that was difficult to refute.
It may already be time to rethink that position, however
As the science behind genetic testing has evolved, it’s easier and easier for investigators to find “trace” DNA at crime scenes. This is genetic martial that is so minuscule – such as a few skin cells – that it may not even be visible to the naked eye. Unfortunately, that also increases the risk that DNA evidence that has merely “wandered away” from its host will be picked up at a crime scene.
For example, consider this real-life scenario: A homeless man was arrested and charged with the home invasion-style murder of a millionaire, despite the fact that the suspect had actually been hospitalized for alcohol poisoning at the time. Yet, trace amounts of his DNA were found on the victim. How could that be possible? The same paramedics who took the homeless man to the hospital in their squad were called to the scene of the wealthy man’s murder. In the process, they carried small amounts of the homeless man’s genetic material with them into the millionaire’s home and contaminated his body with that DNA while working to revive him.
Incidents like those are a reminder that no forensic evidence is above suspicion, and all interpretations are subject to challenge in a court of law. That’s what makes it incredibly important to seek legal guidance before committing to a legal strategy based on the alleged strength of the state’s evidence in a criminal matter.