I was talking to a woman who works in the ticket processing office. She told me their office deals with around 40,000 tickets a month. Many people never bother replying to the letter. They can't summons all of these people to court so they feed the cars details into the computer to see how many times its come to notice. If its got say 5 or more tickets outstanding they send the details to the enquiries section who will attended the registered keepers address. Any others do not get followed up.
However, she showed me a list of the hundreds of ones where the letter had been sent but there had been no reply. She said they randomly pick 10 a month from the list to prosecute for failure to disclose and the rest just get binned.
HOWEVER, this was a processing unit in London which obvious deals with a shed load every month. This may not be the case in some sleepy little backwater that only deals with a few tickets. They may be able to follow them up because of the much lower numbers.
(Just to clarify, i'm not advocating non disclosure, as I think people should cooperate fully with the authorities and observe the legal requirement to disclose the information. This is posted just to highlight the problems with so many people breaking the law and effectively overloading the system

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