Offending and intellectual disability (MEQ)

(i) Epidemiology and method traps. Most people with ID do not offend. Prevalence estimates vary with ID definition (IQ alone vs adaptive criteria), sampling (community services vs police vs prison), and offence definition (allegation vs conviction). Holland and colleagues emphasise relatively low absolute rates of formal CJS contact among people known to ID services despite associations when IQ is treated as a continuous risk marker. Prison diagnosed ID is typically about 0.5–1.5% (Fazel et al.), not the high percentages sometimes claimed from brief screens. Referred forensic samples over-represent early-onset multipurpose careers and sexual/fire-setting pathways.[1][2][6]

(ii) Suggestibility and fitness. Clare and Gudjonsson showed elevated interrogative suggestibility, confabulation and acquiescence in mild learning disability — treat “always agrees with police” as a reliability red flag. Ensure communication supports and local Appropriate Adult/intermediary principles; do not invent procedures. Fitness is present-state and functional against the local legal standard (understand proceedings, instruct counsel, plea, follow evidence). IQ alone is not the test. If deficits are knowledge/skill based, structured restoration training can help selected people with ID (Wall model); reassess after supports.[3][4]

(iii) Offence and risk assessment. Multi-source analysis: staff logs, co-resident statements, prior property offences, substance use, bullying history, and sexual knowledge/consent education — not self-report alone. Structured professional judgment plus criminogenic needs; risk instruments have limited positive predictive value and must not replace formulation (Fazel meta-analysis). Include protective factors and victim–offender overlap (bullying/possible exploitation).[5][6][8]

(iv) RNR-adapted management. Match intensity to risk; target needs (substance use, sexual risk pathway, peer influence, problem-solving, housing stability); adapt delivery (concrete language, visual materials, longer programme, support-worker generalisation). Consider adapted sexual-offence work; anger CBT evidence applies when access allows (Willner). Treat dual diagnosis if present; avoid open-ended antipsychotics for non-psychotic behaviour alone. Safeguard both the defendant and other residents.[6][7][8]

(v) Disposition principles. Prefer least restrictive option consistent with risk: community dual-disability treatment and supervised placement change vs custody. Diversion and mental health/disability pathways are jurisdiction-specific — describe principles only, no invented section numbers. If remanded, plan reception screening, medication continuity, anti-bullying protection, and release transition. Document opinions within referral questions with forensic neutrality.[1][2][4]