When it comes to criminal cases, courts consider DNA evidence as a reliable indication of a person’s guilt or innocence. A technician will collect DNA samples at the scene of the crime, take them to a lab, and test them to look for a potential match. When there is a match, it is usually regarded as irrefutable.
However, opinions regarding the infallibility of DNA evidence have changed over the years. Many researchers call into question the reliability of DNA evidence when it comes to convictions. Here are a few possible issues that may arise and why it is so important for law enforcement to handle samples correctly.
The complexities of DNA collection
Problems with DNA collection can greatly compromise the subsequent results. Sample collection must occur according to established protocols and using sterile equipment to avoid contamination. When there are different types of DNA at a crime scene, technicians must collect and process them separately. Then there is the process for collecting samples from the victim of the crime, which rules out their DNA from that of the assailant or assailants.
The above steps must occur with the proper training and knowledge to ensure accuracy. Misreading a result, mishandling a sample, or confusing two different specimens can lead to an incorrect match. And when it comes to serious crimes, this match can land an innocent person in jail for years to come.
How to avoid issues involving incorrect testing methods
While most DNA evidence is consistently accurate, that is of little comfort to a person wrongly convicted of a crime. That is why so many advocate for a more critical view of the process, particularly within the context of the larger case. When there are other factors at play or conflicting evidence, DNA samples deserve a closer look.
Additionally, automating the process reduces the risk of human error. Better collection and handling of samples, and improved reading of results, can make a huge difference during criminal cases.