A summary of what I have done:
Reply denying any liability, and ask them to substantiate their claim against you.
Unless they actually substantiate the claim against you personally (ie photo of YOU, your signature etc) and not just send you a picture of a car with a computer enhanced number plate :
Follow up your prior response to any follow-up letter from them (email/post to the same address as before) Saying that despite your request, that they have failed to substantiate any claim, so unless they cease all demands and claims you will report them to the police for harassment. Email is good as delivery to their point can be confirmed.
You should also complain to the DVLA that they have released your information to a party who have not given any valid cause for release of your information. This wont get you too far but they will respond and it will be logged. (I am pursuing this so the more complaints the better)
email complaint to : csm.dvla@gtnet.gov.uk
When you receive the fob-off replay, follow up with a complaint to the ICO mail@ico.gsi.gov.uk
against the dvla
Basis for the complaints:
Per Phil Jones, assistant commissioner at the ICO "the DVLA passes on information from its register to third parties for a variety of legitimate reasons but the person or organisation requesting the information must always provide evidence to the DVLA to show why their request is reasonable"
These companies provide no evidence whatsoever to get your details from the DVLA, and the only 'evidence' they have is a poor picture of a car etc, nothing showing the driver.
Do all these and we should be able to both reduce the impact of these folk, and improve the protection of our data, which is extremely poor.