Significance of combustion accelerator traces in criminal investigations of intentionally set vehicle fires

Abstract

Determining the cause of car fires is a combined expert examination conducted as the examination of a burnt car by the experts of the National Forensic Center of the Ministry of Internal Affairs of the Republic of Serbia. The expert examination primarily determines whether the fire occurred as a result of spontaneous combustion or it was either a negligent or an intentionally caused fire - arson. The procedure involves an investigation of the scene of the incident and an expert examination of material retrieved from the scene of the fire or from persons who are suspected to have been present at the scene of the fire. That place contains a lot of personal and material information, possible evidence in the proceedings. The aim of this paper is to point out, based on practical examples, the specific traces showing the use of combustion accelerators, which in criminal investigations unequivocally indicates that the car was set on fire intentionally. Concentric flow trails, droplet flow and obstacle bypass, funnel flow trail, accelerant concentration trail, or uneven burning as a trail, are just some of the variants of combustion accelerator trails. The analysis of such traces on the practical examples has an exceptional didactic value. Accredited laboratories today have validated methods and instruments for detecting the presence of minimal amounts of combustion accelerants in a sample.