EXPERIMENTS IN OR OUT OF COURT TO ILLUSTRATE COMBUSTION OF MATERIALS OR A MODE OF OPERATION REQUIRE DUPLICATION OF THE ORIGINAL FIRE CONDITIONS. FIRE INVESTIGATORS MUST BE CAREFUL TO NOTE RELEVANT CONDITIONS AT THE FIRE SCENE, PRESERVE AS MUCH EVIDENCE AS POSSIBLE, AND ESTABLISH A CHAIN OF CUSTODY FOR ANY PIECE OF EVIDENCE, DATING BACK TO ITS RETRIEVAL AT THE FIRE. ALTHOUGH MANY ARSONISTS REPEAT THEIR CRIMES, EVIDENCE OF FIRES OTHER THAN THE ONE AT TRIAL CANNOT BE ADMITTED UNLESS THE FIRES ARE PHYSICALLY CONNECTED, ESTABLISH INTENT, OR SHOW A COMMON MODE OF OPERATION. ARSON DEFENDANTS OFTEN FACE TWO CASES OF LITIGATION SIMULTANEOUSLY: PROSECUTION BY THE STATE, AND A COUNTERSUIT OF INCENDIARISM FROM THE INSURANCE COMPANY WHEN THE LATTER FINDS OUT THE DEFENDANT IS BEING PROSECUTED. HOWEVER, SINCE DIFFERENT CASES INVOLVE DIFFERENT JURIES, CONVICTED ARSONISTS MAY NONETHELESS BE AWARDED INSURANCE PAYMENTS. BECAUSE CONFESSIONS ARE SELDOM SUFFICIENT TO PROCURE ARSON CONVICTIONS, FIRE INVESTIGATORS ARE WARNED TO COLLECT AND PROTECT AS MUCH CORROBORATING EVIDENCE AS POSSIBLE, AND ARE REMINDED THAT THERE IS NO RULE FIXING HOW MUCH CORROBORATING EVIDENCE IS NEEDED. ADVICE IS ALSO GIVEN ABOUT SIGNED V. ORAL STATEMENTS OR CONFESSIONS AND USING GOVERNMENT REPORTS, HEARSAY, OR POLYGRAPH TESTS AS EVIDENCE. FINALLY, AS ARSON IS SO DIFFICULT TO PROVE, OTHER TYPES OF PROSECUTION ARE DISCUSSED, SUCH AS CRIMINAL NEGLIGENCE, FALSE INFLATION OF INSURANCE CLAIMS, CIVIL LIABILITY, AND SUBROGATION (ALLOWING INSURANCE COMPANIES TO RECOVER CLAIMS PAID OUT FROM THIRD PARTIES WHO START FIRES ACCIDENTLY). FIRE INVESTIGATORS ARE ENCOURAGED TO INVESTIGATE ALL FIRES AS THOROUGHLY AS POSSIBLE TO DEVELOP THEIR INVESTIGATORY SKILLS. FOOTNOTES ARE INCLUDED. (PAP)