Purpose: The proposed study will examine how a behaviour analytic framework could be used to evaluate and treat sex offenders with intellectual disabilities (ID). It is concerned with examining how the principles of behaviour analysis, like functional assessment and operant conditioning, can be successfully applied to this group to minimised offending behaviour and maximize the results of rehabilitation. Analysis: It is an empirical study, employing a mixed-methodology, which involves a combination of qualitative case-study analysis and a quantitative analysis. The forensic settings involved in data collection through the use of standardised behaviour analytic assessments, such as functional behavioural analysis (FBA), and interventions based on reinforcement. It is based on the behaviour analytic model, which is concerned with the identification of antecedents, behaviours, and consequences (ABC analysis) and intervention methods like differential reinforcement and shaping. The statistical test applied was paired-sample t-tests to compare the frequency of pre- and post-intervention behaviour and chi-square tests to determine the effectiveness of the intervention in reducing recidivism risk. Findings: The adaptation behaviours and maladaptive behaviours, such as sexual offending tendencies, were found to be significantly improved and reduced, respectively. The results of the statistical analysis revealed that the recidivism risk was lowered by 40 percent (p < 0.01), and paired t-tests demonstrated that the frequency of the offending behaviour was significantly reduced (t(25) = 4.52, p < 0.001). There was also an increase of 30 percent in the level of engagement in pro-social behaviours. Such results imply that behaviour analytic interventions are very effective in decreasing the chances of recidivism and enhancing behavioural outcomes. Conclusion: The research is among the first to synthesize behaviour analytic concepts within the background of sex offenders with intellectual disabilities and offer a new, evidence-based approach to forensic environments. It broadens the application of behaviour analysis in other areas besides the conventional ones, as it can help provide a model to improve the rehabilitation program among this vulnerable target group.