We've made considerable advancements in the last several decades of forensic science. DNA testing has given us the ability to pinpoint culprits that may have never been caught just a few decades ago.
This opens up the possibility for cold cases like the recent trial of the 1979 Catherine Janet Walsh homicide to finally go to court, and for justice to hopefully be obtained for the victims.
But new evidence doesn’t always mean justice will be cut and dry.
Essential Pittsburgh legal contributor and University of Pittsburgh law professor David Harris, says the most difficult challenge when opening a cold case is tracking down witnesses.
“Oftentimes witnesses die, or they move away and we no longer have that access," says Harris "Other times their memory fades and people just can’t remember details. Human memory can be a big, big problem.”
DNA testing offers a limited perspective as well. In the case of Catherine Janet Walsh, DNA could identify that a suspect was at the scene, but it can't point out when or why they were there.
For some offenses, the statute of limitations may prevent evidence gathered from new forms of forensics from ever being used in a trial. In Harris’ opinion, it is our duty to take a look at existing laws.
“If we don’t respond to [new technology], shame on us. We’ve got to adjust our laws so that science can give us the full benefit."