In criminal proceedings, defense attorneys occasionally attempt to establish that a suspect was not present at the commission of a crime by comparing the suspect' s DNA to the DNA of blood or hair samples taken from the scene of the crime  Although every person' s DNA is unique, DNA tests often fail to distinguish among DNA samples taken from distinct individuals
Hence, it is a mistake to exonerate a suspect simply because that person' s DNA did not match the DNA samples taken from the scene of the crime
It confuses a test that incorrectly identifies DNA samples as coming from the same person with a test that incorrectly shows as coming from different persons samples that come from a single person.