In the fire service we are always expected to work alongside law enforcement. The chain of custody will be the topic of this discussion. In any fire we know to limit overhaul by using thermal imagry camera's. (the smoke pattern on the wall will assist the marshals in locating the cause and help find the starting point. In drug labs, touching anything can mean you contaminate the chain of custody. Our role as firefighter/hazardous materials teams has evolved. We are expected to be vigilant as well as complete the task of fire suppression. Something as simple as picking up a pyrotechnic device that landed against a building (causing the fire) and looking at it will contaminate the chain of custody. In a court of law the judge wants to see a VERY short chain of custody. In White power incidents, we see evidence collection techniques used by Haz Mat teams. There is a 16 hour evidence collection introductory training level that should be achiev3d before you break out your CSI skills. Our job is to locate the source, conduct testing, photograph everything, and then collect more samples. Again, our job is NOT cleanup. Companies are paid large sums of money to clean up these scenes. Anyone who touches or handles ANY potential evidence is to be included in the chain of custody and should be marked as so in the log. All your rubber gloves, trash, and product sampling devices should be all documented, and kept. Any chance a defense attorney has to get their client off the hook, they will exploit. They would not hesistate to try to pin "a bad job" on a firefighters head to get their client free. Quite simply to make this easy, the person collecting the evidence shall maintain control and location of the items until turned over to the proper authorities, and until the law enforcement authoraties have it in their chain of custody (properly packaged, labeled, photo logs submitted and a complete breakdown in a written log is submitted assume the worst, and plan for it as well