"PeterG" wrote in message
...

If a car driver had had a dim light showing you would expect him to
be pulled over, why should it be any different for a cyclist.
Like all road users he should check his light before he made his
journey.

True. However it is possible for a battery to go flat or a bulb to fail
during the journey. How often is one supposed to stop and re-check a light
*during* a journey to make sure that it is *still* correctly lit?

I was surprised how difficult it was to tell, under street lighting, that
one of my headlight bulbs had failed: it wasn't until I came up behind a car
in front that I saw that only one side of his rear end was lit by my lights.
Obviously on an unlit road the lack of one dipped headlight would have been
much more apparent.

I'd checked when I set off that both my lights illuminated the wall that I
park in front of, so I'd done all that I could be reasonably expected to,
and as soon as I discovered the fault I stopped and replaced the bulb from
the spares that I carry.

The cyclist in question was probably prosecuted because he behaved like an
arrogant pillock - whilst it is an offence to have a non-functioning light,
I'm sure the policeman's decision to be reasonable and fair in the
application of the law was swayed by the cyclist's reaction - he brought his
downfall upon himself.