The long inpatient stay is a long-term issue facing the forensic intellectual disability services, which are usually motivated by complicated clinical demands, long delays in placement, and poor transition planning. This paper suggests and analyzes a hierarchical Care Pathway Model that will decrease length of stay by providing admission-based discharge planning, gradual rehabilitation levels, multi-agency transition review, and supervision of the patient post-discharge. The outcome was compared in two 12-month periods in the pre-pathway and post-implementation of the pathways in a low-secure forensic intellectual disability inpatient unit (n = 40 discharges). After implementation, median length of stay fell to 19.3 months and mean length of stay fell to 21.4 months as compared to 27.8 months and 29.5 months respectively. The percentage of admissions greater than 36 months fell to 18% off of 42. There were also service improvements in which the inpatient incident frequency was lesser, the time of placement delays was less, the number of milestones completed before discharge was more, and the readmission rates after 12 months. The cumulative analysis of distribution showed that during the earlier part of the post-implementation period, a higher percentage of patients were discharged, which means that there was an improvement in the pathway progression. The results indicate that pre-admission and pre-discharge care planning can promote the efficiency of discharge and rehabilitation congruency in forensic intellectual disability care. The suggested model provides a scaling model of reducing lengthy inpatient stay and it can be further validated and long-term outcome assessed across multiple sites.