http://www.theanswerbank.co.uk/Law/Question382 753.html
As the previous answer states, this is an absolute offence - either you did it or didn't - but the court does have some leeway in sentencing. A fixed penalty notice can be given but you have to accept the �200.00 and six points which in this case doesn't sound like the best option.
Definitely take legal advice. There should be a duty solicitor at the court although it'd probably be better to take advice before.
From the police point of view there is a duty to report it - if nothing else, if you had had an accidentg and it becaem apparent that the officer had stopped you and hadn't acted (there's always a computer trail with any checks done) then there would have been comeback.
The officer would have been sympathetic. It's rare to find someone who has no insurance through no fault of their own (as in your case). Usually it's becasue they can't be bbothered, don't see why they should follow the law, don't see why they should act responsibly etc. Rant over.
Good luck.