Forensic Sciences and Forensic Identification

Thirty years ago, forensic investigation was spoken of almost religiously, a multibranched philosophy that could—with enough practice, enough patience, and enough attention to detail—positively identify who committed a crime beyond a reasonable doubt. The abilities of forensic experts to solve crimes were so strongly believed that they became the subject of countless television shows, both real and fictional. “CSI” alone has four spin-off series, each more spectacular than the last, all of them depicting dedicated and (more importantly) altogether unerring crime scene analysts who always found their man by the end of the hour. Forensic investigation was seen, in the eyes of the public at least, as nothing short of a miracle for police work. It could be used to solve cold cases, which had previously stymied law enforcement; it could completely destroy a defendant's alibi; it could definitively prove guilt by analyzing a piece of evidence invisible to the naked eye. This chapter will review the principles and practice of the forensic sciences from law enforcement, prosecution, and defense perspectives.