Decriminalised parking enforcement (DPE) is the name given in the United Kingdom to the civil enforcement of car parking regulations, carried out by civil enforcement officers, operating on behalf of either a local authority or a private firm. The Road Traffic Act 1991 (c. 40) provided for the decriminalisation of parking-related contraventions committed within controlled parking zones (CPZ) administered by local councils across the UK. The CPZs under the control of the local councils are also referred to as yellow routes and they can be easily identified with yellow lines marked on the roads with relevant time plates. Some councils employ parking attendants to enforce their CPZs directly while others contract their on-street parking enforcement to private companies.