Durham Cathedral North door showing the Sanctuary Knocker.

Durham Cathedral was also a centre for criminals seeking sanctuary. A criminal would bang the sanctuary knocker at the north door on Palace Green to alert one of the watchmen. They would be admitted into the cathedral, and offered sanctuary for 37 days. They were obliged to confess the details of their crime to the coroner, and they had to change their clothes for a black robe with a yellow cross on the shoulder. By the end of the 37 days, during which time they would be looked after at the expense of the church, the criminal had to leave the country by an assigned port. Hartlepool was the port assigned to Durham. If they did not do this, or deviated from the King's highway en route, they were executed.