Officers should ensure that DNA evidence remains dry and at room temperature and secured in paper bags or envelopes that are properly sealed and labeled. They should never place DNA evidence in plastic containers, direct sunlight, or a car trunk. They must also ensure that they do not contaminate the evidence. Meeting legal and scientific requirements for admissibility in court requires a proper chain of custody and numerous other procedures to preserve the evidence properly. The microscopic slides serve as useful reservoirs of crucial evidence for testing years later. In addition, new technology in DNA analysis allows crime laboratories to exchange and compare DNA profiles. This biological evidence can assist in the successful identification of the perpetrator as well as in the exoneration of a wrongly convicted person. Checklists, photographs, and reference notes