ABSTRACT
This chapter proposes the basic steps to follow in carrying out a systematic fire investigation. As long as the potential exists for the fire to be determined as incendiary, site security should be in place, along with mandatory procedures designed to protect the integrity of any criminal prosecution. Unless the investigator finds evidence of human involvement, the data and the evidence support an accidental hypothesis for the initial classification of the fire cause. The controlling legal authority of a fire investigator's right of entry is the Supreme Court's interpretation of the Fourth Amendment in two Michigan cases, Michigan v. Tyler and Michigan v. Clifford. If one is keeping a file on a particular fire investigation, one should keep all the data in that file. Record keeping should be consistent, and destruction of documents should be avoided. The circumstantial evidence from which fire investigators draw inferences is seldom as clear as the footprints in the snow.
