First used to convict a killer in 1911, fingerprint analysis remains a viable forensic tool a century later. Tom Bush, an expert at an FBI location in West Virginia that processes 140,000 fingerprints each day, claims that the system is more than 98 percent accurate. Fingerprints represent very compelling evidence in criminal cases, so it’s important to be able to tell the difference between prints.
Latent print examiners can analyze fingerprints on clear objects like windows and drinking glasses visually with the proper lighting. However, for more in-depth analysis and for opaque objects, print examiners transfer prints to sticky tape with a technique called lifting. Apply a dark makeup powder with a soft, fine brush to the printed area. Completely cover it while taking care not to smudge the print, then blow away the excess powder. Press a piece of sticky tape on the powdered area, then remove it and stick it on a piece of paper.
Fingerprint Analysis Pros
Fingerprint analysis provides a way to convict criminals based on hard evidence without dealing directly with more gruesome details often associated with major crimes, like bone and blood DNA evidence. Investigators and prosecuting attorneys alike greatly value fingerprint evidence and its ability to sway judges and juries toward a conviction. Sometimes a court case hinges on fingerprint evidence, and in these circumstances, it often means the difference between a conviction and a criminal being released.
Fingerprint Analysis Cons
One of the flaws inherent to fingerprint analysis actually lies in how convincing the evidence can be. Fingerprints at the crime scene that match the suspects carry so much weight in the eyes of judges and juries that it can be difficult for defending lawyers to exonerate their clients. Unfortunately, the history of fingerprint analysis is littered with cases of the wrongly convicted. This can happen as a result of framing by the true perpetrator, a falsely detected print match or just misinformation.
Fingerprint analysis has undoubtedly had a major impact on the criminal justice system. For a long time, this form of evidence was considered ironclad, and sealed the fate of many perpetrators. However, a few examples exist where judges overruled or barred print evidence. U.S. District Judge Louis Pollak did just that in a Philadelphia murder trial of 2002 on the basis that such testimony isn’t based firmly on science, and no definitive statistical study has shown how often print examiners might be wrong. Such rulings continue to make fingerprint analysis a controversial form of evidence, but for now it still holds weight in most courtrooms.