Isn't there a law that requires cars parked on roads with a speed limit of more than 30mph after dark to have a light on? Something rings a bell about an over zealous (or bored) copper ticketing a load of cars on the Leeds Outer Ring Road one night for failing to show a light and the outcry in the local paper, with his Inspector subsequently canceling all the tickets and offering him "words of advice"...
Yep you're right. Taken from askthepolice:
"Q386: What are the rules for parking a car at night?
You must not park on a road at night facing against the direction of the traffic flow unless in a recognised parking space.
All vehicles must display parking lights when parked on a road or a lay-by on a road with a speed limit greater than 30 mph (48 km/h).
Cars, goods vehicles not exceeding 2500 kg unladen weight, invalid carriages, motorcycles and pedal cycles may be parked without lights on a road (or lay-by) with a speed limit of 30 mph (48 km/h) or less if they are:
- at least 10 metres (32 feet) away from any junction, close to the kerb and facing in the direction of the traffic flow
- in a recognised parking place or lay-by.