For decades now, DNA evidence has held the prime spot as the ultimate evidence. It is scientific and impossible to dispute. However, this is now in question as science advances and DNA evidence actually becomes less reliable as a result. If you face criminal charges and the prosecution is relying heavily on DNA evidence, then it is a good time to become familiar with the issues with this type of evidence.
According to Forbes, there are many issues with the nature of DNA that makes it an unreliable evidence source. In the beginning when DNA collection and analysis were new, it required a large sample to come to a definitive result. These days, it only takes a very small sample to return DNA results, which is the problem.
Small samples lead to bad results
Being able to identify someone’s DNA from a very small sample means that it is very easy to place almost anyone at the scene of a crime as long as that person has ever been in the location. Wherever you go, you leave small traces of your DNA. It can stick around for quite a while. This means that if you go into a store on Monday and on Wednesday a murder occurs there, the chances are good, investigators will find your DNA at the scene.
Not only can you leave your DNA behind on objects and surfaces but also on people. So, if you knew a murder victim, then your DNA may be on that person. You can also transfer other people’s DNA to another person. This means that if your best friend is the murder victim, he or she could end up with DNA transfers from you, your spouse and your boss. You can even transfer DNA you pick up from a surface.
So, while DNA identification is quite accurate, its use as evidence to put a person at the scene of a crime or even in contact with a victim is not reliable.