The firesetting offence chain for adults with intellectual and other developmental disabilities

Background: The aims of the research are to: 1) validate Barnouxet al.'s (2015) and Tyler et al.'s (2014) micro-level theories of adult firesetting with a sample of adults with intellectual and developmental disabilities who have set fires; and 2) to offer a unified descriptive model of the offence chain for adults with intellectual and other developmental disabilities who set fires. Method: Thirteen adults in England with intellectual and other developmental disabilities were interviewed about the affective, cognitive, behavioural, and contextual factors leading up to and surrounding a recorded firesetting incident. Offence account interviews were analysed using a Grounded Theory approach. Results: The resulting model consists of four main phases: 1) background, 2) early adulthood, 3) pre-offence period, and 4) offence, and post-offence period. The model accounts for unique precursors to firesetting within this population, including mental health deterioration, poor problem solving and new motivations for firesetting. Conclusions: The theoretical model seeks to explain the contributing factors leading to a single incident of firesetting for adults with intellectual and other developmental disabilities. The findings provide researchers and practitioners with a useful resource to inform assessment and treatment practice, as well as a theoretical grounding in which to base future research.