There have been many kinds of evidence over the years that have been used to convict individuals accused of a crime. Back in the 19th century, phrenology was a type of study that claimed to be able to understand an individual’s psychological makeup on the basis of the shape of their skull. The brain supposedly formed various bumps, grooves and shapes on a person’s skull and those things could tell law enforcement if the individual had criminal intent or tendencies.
That particular ‘science’ was actually used, not only in the 19th century, but also into the 20th century in the USA. In 1927 Ruth Snyder was accused of killing her husband. A well-known phrenologist, Dr. Edgar Beall was called in to perform a reading on Ruth Snyder. Partially based on Dr. Beall’s testimony Ruth Snyder was convicted and executed in 1928. The following link is an explanation of the Ruth Snyder case:
The last century involved other debatable types of evidence that led to convictions of several people. Subsequent investigations have often shown that these types of evidence in specific cases as being inaccurate, if not downright false. Although other evidence may be included into the trial that proves or disproves guilt, certain types of information is often presented and accepted by the jury as being ‘better’ than other evidence. It’s unfortunate when a jury accepts weak evidence by the Prosecution simply because they aren’t aware of the problems that may be inherent in such evidence.
Perhaps one of the most common examples is false identifications by eye witnesses. In the Police Academy the instructors tried to show us how eyewitness evidence can be very wrong by providing an abrupt, noisy and confusing activity where the entire classroom wrote down their remembrance of what had just occurred and their description of the offender(s). The wildly different tales written by 30+ recruits should have made very clear to us that eyewitness testimony may have problems unless reinforced by scientific evidence.
Unfortunately, many of us, me included, often forgot that lesson from the Academy. While none of my casual acceptances of eyewitnesses’ testimony were ever involved a situation where there was any type of wrongful convictions, it’s important to note that sometimes even the best of intentions may go awry in the heat of the moment. There are, however, several cases of convictions based on eyewitness testimony that were later overturned by scientific evidence.
It is important not to denigrate the eyewitness who is sure of what he or she saw. But it is wise to realize that our eyes and brains are not cameras and we can make very human mistakes. Just as important, what a person sees in a fleeting moment in a fast-acting situation such as a bank robbery is often less accurate than something seen in an up-close and personal situation such as a rape. Yet, there are even exceptions to that situation. Here are links to information about problems with eyewitness identification in such cases:
Other evidence often used in the prosecution of an offender is the confession by the accused. In some cases the accused has actually made a confession, a false confession. As a person with few ties to the criminal justice system, you may swear that you’d never be stupid enough to confess to something you didn’t do. The problem is that not all people who make false confessions are wacko, although there are many of those who confess. I was working the station desk when someone came in a tried to confess to a murder that hadn’t even happened.
However, there’s an entire science now evolving over the concept that sane, innocent people do, in fact, falsely confess to a crime. Often this happens to people with low mental ability, teenagers who’ve never been involved with the police and others who may have been influenced by the type of interrogation they’ve gone through or who believe that they will get to go home if they tell the police what they want to hear. There is a good reason why I’m a firm believer in taping, not only the actual confession but the entire interrogation. Taping entire interrogations, despite resistance by the police themselves, is a way to also protect the police of being falsely accused of harsh interrogation methods.
There’s a fairly impressive list of convictions made when juries accept a confession at face-value rather than look at other evidence that can provide scientific basis for the confession. The following links show how false confessions can lead to a true travesty of justice:
Another questionable type of evidence is tooth impressions by the offenders. This was even a topic in a ‘Columbo’ TV show and was initially greeted by prosecutors as a great step forward in scientific evidence. The majority of teeth impressions are made when the offender bites a victim. The fact is that many, if not most, bite marks are very inaccurate if only because the surface that is being bitten, human flesh, is malleable and easily moved. A forensic dentist has to be very careful not to make a rash and
positive identification based solely on the tooth impressions of a suspect. Perhaps the best known case in recent history was the one involving the ‘Snaggletooth Killer’ Ray Krone. This link alone should scare anyone who thinks that tooth
impressions are the end all-be all of evidence of the guilt of a person: http://forejustice.org/wc/ray_krone_JD_vol2_i9.htm
There are a multitude of other types of evidence that can be either misused or misunderstood when used at trial. An excellent place to learn about the various ways that evidence, either because of its imperfections or its misuse, is questionable at best or pseudo science that leads to unwarranted convictions. To understand these things better, check out The Innocence Project at the following link: http://www.innocenceproject.org/