n. Deoxyribonucleic acid, which is a chromosomal double chain that exists in the nucleus of each living cell. DNA determines an individual’s hereditary characteristics and can be used to distinguish and identify an individual from another person. This becomes critical when blood, hair, skin, or any other part of the body is used to prove one’s involvement, or lack of involvement, in a crime scene. DNA tests have been used to release a convicted killer on death row who did not commit a crime, but debate continues over whether DNA evidence is scientifically certain enough to be admitted in trials. The current trend is to allow admission.