Autism and lone-actor grievance-fueled violence: A rapid evidence assessment of best practice psychological treatment.

Lone-actor grievance-fueled violence presents a growing challenge for security and mental health systems, with emerging evidence suggesting individuals with autism spectrum disorder may be disproportionately represented in this offender group.This rapid evidence assessment (REA) synthesizes current research on psychological interventions aimed at reducing loneactor grievance-fueled violence risk in individuals with autism spectrum disorder.Eighteen studies were reviewed, but only two directly evaluated interventions tailored for autistic individuals.Most studies were methodologically weak, lacked manualized interventions, and offered limited empirical data.Programs such as the Diamant resilience intervention and integrative complexity showed promising results with modest but consistent improvements in autism spectrum disorder-specific vulnerabilities such as tolerance of ambiguity, cognitive flexibility, and attitudes associated with violent extremism.The findings highlight a critical need for high-quality, trauma-informed, neurodiversity affirming research to guide clinical practice, policy, and future intervention development to ethically and effectively address the risk of lone-actor grievance-fueled violence in neurodivergent individuals. Public Significance StatementAutistic individuals are increasingly encountered within threat assessment and fixated threat pathways for lone-actor grievance-fueled violence, yet there is little evidence to guide psychologically informed intervention.This review found that current responses predominantly emphasize monitoring and case management, while available psychological interventions inconsistently target the grievance fixation, cognitive rigidity, and social-emotional vulnerabilities central to autism-related risk formulations.The findings highlight a critical need for formulation-driven, autism-informed psychological treatment integrated within structured professional judgment and multidisciplinary threat assessment frameworks.