Under the previous system, parking offences were breaches of the criminal law enforceable through the criminal justice system.

The 1991 Road Traffic Act (RTA'91) allows a Highway Authority (Essex County Council) to apply to the Secretary of State to establish Special Parking Areas (SPA's) which, once approved, transfers the power to enforce on-street parking restriction in the defined area from the Police to the Highway Authority.

The enforcement of Penalty Charge Notices (PCN's) issued to motorists under DPE becomes a civil debt owed to the Local Authority as opposed to a breach of the criminal law. Therefore "decriminalising" the parking offence.

The Traffic Management Act 2004 replaces the RTA 91. Decriminalised Parking Enforcement becomes Civil Parking Enforcement, Parking Attendants become Civil Enforcement Officers and Special Parking Areas become Civil Parking Areas. A PCN is still a civil debt.