The management of people with diabetes in police custody has received little attention. Few guidelines are available for police officers to manage people with diabetes who are being detained in custody, despite the risk of metabolic derangement occurring in this situation. The use of drugs and alcohol by the detainee prior to arrest may confuse identification of the symptoms and signs of hyper‐ and hypoglycaemia, and emergency treatment in hospital may be required because of inadequate or inappropriate management while in custody. To evaluate current practice, to identify problem areas and to help implement change, a liaison was established between a specialist diabetes service and the local police force. An experienced diabetes specialist nurse identified problem areas in collaboration with the police custodial team and the forensic nursing service. Input from specialist medical and dietetic staff was sought and issues pertaining to awareness, staff training, equipment and dietary provision were evaluated. This liaison initiative led to the implementation of training for police staff to deal with people with diabetes who require insulin therapy, in blood glucose monitoring and in the management of diabetic emergencies. Equipment for diabetic management in the police station was upgraded, and training provided for its use. Police awareness of the potential problems associated with diabetes was heightened. Audit and further evaluation of these changes are being performed to ensure that these acquired skills and staff competence are maintained. Copyright © 2008 John Wiley & Sons.