DNA Testing And How It Has Changed Criminal Proceedings


DNA, which is also called deoxyribonucleic acid encloses within itself all the genetic details of a living being. It defines a person’s characteristics, his race and his entire body genetic build-up. A person carries the same DNA in every cell of his body. Since each part of human body is made up of cells, any material or part of his body left behind by the person contains his DNA details. Any material of his body like hair, skin, nails, blood, semen, perspiration, mucus, teeth or saliva can be used to extract a person’s DNA details.

Since last few years lot of development has been noticed in the field of criminal proceedings. DNA evaluation is being used extensively to solve the crime cases and find the culprit. This kind of DNA Testing is known as DNA Profiling. DNA profiling method was brought into practice for the first time in the University of Leicester, United Kingdom by Sir Alec Jefferys. It is a method used by forensic scientists to determine a person through the DNA details found on the crime scene. DNA profiles are little sets of variations found in DNA structures. They are very different in the people who are not related.

DNA details are used in criminal cases in either of two ways. In the criminal proceedings where a suspect is found, the DNA testing is done to match the DNA details of the suspect with the DNA details found on the crime scene. The readings are used in evaluating the suspect. In other cases where no suspect is found, the biological evidences and DNA samplings collected from the crime scene are used to compare with the DNA profiles of offenders and criminals database. Crime scene evidences are matched with the evidences found in other crime scenes from the past maintained in the database.

During 1980s, a foundation for a system was laid by federal government that included DNA Database storage on national, state and local level. It also allowed inter-transmission of these databases. This system is known as CODIS, in other words, Combined DNA Index System. The DNA profiles that are maintained in CODIS are available across the country to law enforcement agencies. The system is capable of comparing crime scene evidences with those found from different crime scenes. This helps in identifying serial criminals. DNA profiles provide a very accurate data unless tempered with.

The DNA testing in criminal investigation is being done extensively in the recent years. DNA testing has facilitated law enforcers to identify criminals even in the complicated crime cases. While, on other hand, DNA testing has also helped in proving the many convicted people innocent.