The multi-component model of harmful sexual behaviour for people with autism and co-morbid intellectual disabilities – a theory and practice guide

Worthington, Rachel Elizabeth (2019) The multi-component model of harmful sexual behaviour for people with autism and co-morbid intellectual disabilities – a theory and practice guide. The Journal of Forensic Practice, 21 (1). pp. 1-13. ISSN 2050-8794

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The purpose of this paper is to explore to what extent neuro-typical theories of sexual offending apply to clients with Levels 2 and 3 autism with a co-morbid intellectual disability (ID). The paper develops a model of harmful sexual behaviour (HSB) for this client group and makes suggestions for how these behaviours can be understood and reduced.

The revised Integrated Theory of Sexual Offending (ITSO) (Ward and Beech, 2016) is used as a starting framework to understand HSB in this client group. This attends to specific neuropsychological systems, brain development, motivation and emotional processing.

The revised ITSO has some utility in understanding HSB in this client group. This is improved when neuro-atypical specific state factors are identified. Practical ways of establishing these state factors are made which attend to the function of the behaviour in line with “Good Lives” model of rehabilitation.

Research limitations/implications
Recommendations for ways in which the function of HSB in this client group can be identified are made as well as recommendations for how treatment can be tailored dependent on the function of behaviour in this client group.

Practical implications
The paper makes practical recommendations for how interventions for people with ID and autism in line with Ward, Clack and Haig’s (2016) Abductive Theory of Method which noted that interventions should be adopted to consider wider explanations for offending thus acknowledging that treatment could extend beyond cognitive behavioural therapy for clinical phenomena. Future treatments for clients with autism and LD are suggested which attend to sensory needs, teaching alternative communication strategies for seeking out “deep pressure” or attention in ways that do not involve sexual offending, using picture communication, information technology or Makaton to communicate needs or using social stories to explain the consequences of behaviour. In addition, neuro-atypical interventions which attend to the neuropsychological functioning of clients could also be included in treatment for neuro-typical clients, thus ensuring that interventions attend to every aspect of the ITSO and not purely clinical phenomena.

Social implications
Enhancing treatment interventions for clients with ID and autism could both reduce risk and enhance quality of life for this client group.

Much of the work to date exploring HSB in clients with autism has attended to clients with Level 1 autism or those without an additional ID. This paper provides practitioners with a theory upon which to understand HSB in clients with a dual diagnosis of Levels 2/3 autism and an ID as well as practical recommendations for reducing HSB in this client group.

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