Arson is the fire of the mind. It is the legal fusion of a chemical reaction with human intent. And yet, scientific investigations are calling into question these forensic judgments. So it is that fire science can rebalance the scales of justice.1

In one generation, the canons of arson investigation have been rewritten by the scientific method2 and codified by the National Fire Protection Association (NFPA) in “NFPA 921: Guide for Fire and Explosion Investigations” (current ed. 2011; next ed. 2014).3