Motorists are advised to park in the marked white lines of a marked parking bay and not to double park their vehicle on the highway.
If a motor vehicle is double parked this means it is parked adjacent to another vehicle which is correctly parked in a bay; this may cause danger or be a hazard to other road users.
The Highway code advises the following:
You MUST NOT leave your vehicle or trailer in a dangerous position or where it causes any unnecessary obstruction of the road.
If a motor vehicle is double parked a Civil Enforcement Officer (CEO) will issue a Penalty Charge Notice (PCN) for the following reason, Vehicle parked more than 50 centimetres from the kerb