This “Nova” documentary explores whether criminals are born or made, whether some people are more prone to be violent than others, takes a trip to a “body farm” at Texas State University to explore the effect an environment has on a dead body, and explores the one hundred year old practice of polygraph exams.
A criminologist at Florida State University named Kevin M. Beaver evaluated the DNA of 1,000 men in an effort to discover the presence of a gene or genetic pattern that caused violence. He did discover a gene, dubbed “The Warrior Gene” that seemed to predispose men to violent tendencies, but also found that a man may possess this gene, but that it alone wouldn’t cause him to be more violent-other factors such as the environment the man grew up in made a difference as well. A positive, nurturing, caring environment may very well be the difference between a man who becomes violent and one who doesn’t. Beaver estimates that 1/3 of men have this “Warrior Gene”.
The body farm at Texas State University helps forensics experts learn the impact of the impact the environment can have on a the decay of a dead body. This may seem like gruesome work, but it is essential in helping other forensics experts and crime scene analysis experts determine the time of death of a victim, and be able to more accurately pinpoint that time-frame can rule in or rule out certain suspects (if a crime has occurred) and credit or discredit the credibility of someone’s alibi. The body farm’s location in the hot, humid Texas weather helps researchers as well. For instance: a body that has been left to decay in the sun will actually mummify instead of completely decompose, whereas a body that has been left in the shade will decompose at a much faster rate. Researchers are also able to evaluate the timing and effects of rigor mortis (muscle rigidity) in a dead body, and have learned that it actually occurs several times over the course of a few days, instead of just a few hours after death as previously thought. All of this information is also hugely useful to medical examiners, who can now more accurately determine causes, times, and dates of death.
Polygraph exams have been used for nearly a century to determine whether or not someone is being truthful, and is based on the concept that lying causes stress within the body. The problems with this is that true psychopaths have no problem lying, and so doing so causes no stress within their bodies; on the flip side, an innocent person being subjected to a polygraph may be unnaturally stressed, which can also cause false results. Because of these issues, the validity and reliability of this test has been called into serious question, which has fueled further research into more credible tests to weed out deceptive people from truthful ones.