If you’ve ever watched “Nova” on PBS, you know that it’s a documentary which covers a very wide range of topics, meaning everything from modern science, politics, world news, culture, and controversial topics are fair game. This particular episode discussed and questioned the validity and reliability of some of the most well-known, often-used, most relied upon forensic crime-solving techniques. The majority of the most relied upon forensic technology is actually close to a hundred years old, and sometimes older. So, is it time to do some updating and question century-old technology? The techniques that were discussed are: fingerprinting, dental evidence, blood spatter analysis, and autopsies.
The show posed the question of the true uniqueness of fingerprints. In other words, does each and every single person in the world have a completely distinct fingerprint, or are there similarities in fingerprints that can potentially accuse, try, convict and imprison a completely innocent person for a crime? Scientists are working on developing techniques that look deeper into an individual fingerprint, beyond the grooves and indentations that are easily visible to the naked eye, to find more minute differences so the victim can be correctly identified and the person who does prison time for a crime is truly the guilty party.
In the case of bite mark analysis, the same question applies: is it possible that no two people can possibly have the same dental records or bite marks? Odontologists (dentists who study bite impressions for the purpose of making positive or negative identifications) have even begun to question the reliability of this particular technique.
Blood spatter analysis can tell crime scene investigators numerous things: the type of weapon used, the types of injuries that were inflicted on the victim and/or suspect, which is especially important if there is no body present at the crime scene, and the brutality of the crime. For example: blood spurts can indicate a severed artery, and blood spatter can indicate an impact blow.
Finally, technology such as CT scans and MRIs are being used by scientists in Sweden to develop cutting edge ways of doing autopsies that don’t disturb the body in the process. By using these scans, the body never needs to be removed from the body bag, and a 3D image can be produced without destroying or disturbing key evidence in the meantime.
All of these techniques have come into question because forensics is based on human interpretation, and because humans do the interpreting, there are bound to be errors. Forensic scientists are working to put the “science” back in to forensic science.