On the state level, Cohasset is represented in the Massachusetts House of Representatives by Joan Meschino as a part of the Third Plymouth district, which includes Hingham, Hull and Scituate. The town is represented in the Massachusetts Senate by Patrick O'Connor as a part of the Plymouth and Norfolk district, which includes the towns of Duxbury, Hingham, Hull, Marshfield, Norwell, Scituate and Weymouth. The town is patrolled on a secondary basis by the First (Norwell) Barracks of Troop D of the Massachusetts State Police.