Fire investigation, sometimes referred to as origin and cause investigation, is the analysis of fire-related incidents. After firefighters extinguish a fire, an investigation is launched to determine the origin and cause of the fire or explosion. Investigations of such incidents require a systematic approach and knowledge of basic fire science. Fire investigators conduct their investigations using a systematic approach. Fire/Arson Investigators compile evidence and information to determine criminal intent. They will interview witnesses and or suspect(s) to obtain reasonable suspicion and or probable cause to charge a suspect(s) with the crime.