The Oxford University Police, or Oxford University Constables (popularly known as Bulldogs), was the private police force of the University of Oxford between 1829 and 2003. They carried warrant cards and were empowered to act as police officers within the University precincts and within areas of Oxford within four miles of any University building. As of 2001 the force existed as a private constabulary (a non-Home Office police force) with 40 sworn constables. They were widely recognised for the bowler hats which formed part of their uniform, and formerly had the duty of patrolling outside the Examination Schools alongside the University Proctors, the officials responsible for discipline in the University. They were abolished by the University Council in 2003.
The power of the university to attest constables was granted by the Universities Act 1825, making the University Police among the oldest police forces in the United Kingdom. In 1829, the same year that the Metropolitan Police Service was established by then-Home Secretary Sir Robert Peel, the Vice-Chancellor of Oxford University signed the "Plan for the Establishment of an Efficient University Police", formalising the powers and duties of the University Constables. They were supervised by the University Proctors, and had disciplinary powers over students.
Until the end of the Second World War, the Constables were considered to be in loco parentis with regard to students of the University, giving them broad disciplinary powers to enforce University rules and regulations.