We have had a lot of these through court recently, it seems the latest mod is to wire your sidelights so that they can be switched off and you have just headlights on at the front of the car. That gets you 3 points and a fine because the law is that headlights, sidelights, tail lights, brake lights, indicators and number plate lamps must all work at all times.
the relevant law is :-
regulation 23(1) Road Vehicles Lighting Regulations 1989
section 42 Road traffic Act 1988
schedule 2 Road traffic Offenders Act 1988