Twenty years ago, the O.J. Simpson murder trial shed a glaring light upon the flawed forensic and evidence gathering work of the Los Angeles Police Department. The highly publicized trial offered the world of law enforcement a textbook example of what not to do while processing evidence at a crime scene. At trial, where Simpson faced murder charges for allegedly killing his ex-wife, Nicole Brown Simpson, and her friend, Ronald Goldman, Simpson’s defense attorney destroyed the prosecution’s case by exposing problems with the Los Angeles Police Department’s handling of evidence. Among the lessons learned by the Los Angeles Police Department was to account for all evidence and log it onto the evidence books, and to be always be honest with the jury, even if this honest approach would hurt the government’s case. O.J. Simpson’s defense attorney, Johnnie Cochran, referred to the LAPD scientific investigations division as a “cesspool of contamination” for sloppy evidence handling. After Simpson’s acquittal on murder charges, LAPD scientific investigations division made significant changes. The crime lab received more funding and additional staff. In 1997, the lab was accredited. Other changes included:
Documentation. In 1994, the crime lab did not routinely document its handling of the evidence. Now, the lab requires its staff to take detailed notes to document all of their forensic work so that information is memorialized instead of left to memory of the technicians.
Chain of Custody. During the Simpson trial, there was a great deal of evidence that prosecution sought to produce at trial. However, the source of that evidence was recorded and could not be explained. Today, the police are required to maintain a clear and accurate record of the source of the evidence, and what happened to the evidence at every stage after its discovery.
Careful Examination of Evidence. During the OJ murder investigation, no one noticed any blood on a pair of socks that were collected from Simpson’s bedroom until two months later when the socks were examined in the crime lab. Defense experts suggested at trial that the blood was smeared on the socks while they were lying flat, not while someone was wearing them.
Proper Evidence Handling. Forensic technicians were criticized for improperly packaging evidence samples and leaving them in a hot van on a summer day. A rookie technician had collected most of the evidence in the 1994 murder case. Today, the lab uses barcodes to scan and track evidence. Crime scenes are also tightly controlled. Trainees, like the one who collected the evidence in the Simpson case, are no longer allowed to handle evidence directly. Instead, trained technicians handle the evidence while trainees watch.
Contamination of Evidence. In 1994, a police detective took a blood sample from Simpson, and then carried the vial of Simpson’s blood in his pocket, back to the crime scenes. At trial, the defense suggested that the blood was brought back to the crime scene for the purposes of planting that evidence at the scene. Today, police are not allowed to re-enter crime scenes while carrying evidence. The evidence is to be booked immediately so that it can be secured.