Introduction

Fire plays a vital role in the survival of not only early humans but also modern humans. Humans have used fire in rituals, cooking, generating heat and light, signalling, propulsion purposes, forging, cremation, and as a weapon or mode of destruction (John, 2016). The destruction of physical evidence, so important for identification and crime reconstruction, remains a frustrating problem (Nataraja, 2008). The primary aim of any forensic fire investigator is to find out the origin and cause of the fire. The cause of the fire may be accidental, arson, natural calamities and even unknown causes. Arson is an intentional set fire on one's or others' property. The investigator should observe and mentally note the scene condition, any visible victims, the damage caused by the fire, and any witnesses or bystanders. The initial observation stage can contribute to the investigation, no matter how small the details, which will lead the investigators on the right path and help them decide if the fire was caused intentionally (David, 2019).

The three key elements to be considered for arson include: i) there has been a burning of property, ii) the burning is incendiary in origin and iii) the burning was started with the intent of destroying the property (Lentini, 2012). The National Centre for Analysis for Violent Crime, USA, have classified the motives for arson as i) vandalism, ii) excitement, iii) revenge, iv) profit, v) crime concealment, and vi) extremism and to prove the commission of arson crime, the cause of the fire has to be determined (Quintiere, 2006). From a psychological perspective, a fire setting is viewed as a function of a disturbed personality.

Therefore, arson may be viewed as a mental health problem and not a criminal act. One of the most frequent emotions acted out by expressive arsonists is anger. Psychologists have stated that one of the reasons many offenders commit arson is because these pathological individuals redirect their anger onto buildings of owners and even parents or relatives, as they see them as easier targets and a way to channel all of their aggression (Jackson et al., 1987).