The DVLA is selling drivers’ names and addresses to clamping companies that break industry rules by charging drivers more than £500 for minor parking breaches, an investigation by The Times has established.

The agency made more than £4 million last year by selling the details of 1.6 million drivers. It sold 900 names and addresses to Newline Securities and Parking Control Management, both of which have repeatedly double-charged drivers for parking breaches and inflated bills by adding spurious charges.

Newline left a family stranded overnight after seizing a car and refusing to allow the owner to retrieve his house keys. PCM charged an elderly couple £375 after they parked for 30 minutes outside a boarded-up office.

The agency has continued to sell drivers’ details to the companies despite being aware of their behaviour. This contradicts the agency’s claim that it carefully vets companies seeking access to the vehicle register. The agency also claims that it denies access to companies that have breached the industry code on parking enforcement.

Parking companies seek drivers’ names and addresses when they have been unable to clamp a vehicle. They use closed-circuit television to read numberplates and, having obtained the owner’s details from the DVLA, send demands for payment in the post.

If the driver fails to pay, the companies multiply the charge and send debt collectors to people’s homes. There is no right of appeal to an independent body, as there is for parking fines incurred on the public highway.

The DVLA offers parking companies two ways of obtaining drivers’ details: they can either apply manually for each individual address or be granted automatic access via an electronic link to the entire register.

The DVLA claims that there are safeguards covering each approach. Companies seeking automatic access must sign up to the British Parking Association’s (BPA) self-governing industry code.

Usage of the automatic route has doubled in the past five years, with companies obtaining names and addresses of 1.37 million drivers this way in the year to the end of March.

With manual applications, the companies merely have to show that they have a contract to enforce parking on private land. The DVLA admits the manual approach is open to abuse and is proposing to require all applicants, by either route, to be BPA members.

However, The Times has obtained evidence that the BPA fails to enforce its code and ignores evidence of breaches by its members, including Newline and PCM.

The owner of PCM, David Blake, sits on the BPA panel, which is supposed to ensure fair treatment for drivers.

Newline charged Panos Eliades £532 to retrieve his car after he parked on a private road in North London. Newline charged separate fees for clamping and removal, even though the BPA code states that only one fee can be imposed if the car is removed within three hours of being clamped.

The BPA has admitted that PCM and Newline breached its code but it is refusing to suspend or expel either company.

The DVLA states on its website that “failure to comply [with the BPA code] could result in suspension and expulsion, and mean that they could no longer apply for information from the DVLA vehicle record”.

Norman Baker, Liberal Democrat transport spokesman, said: “The DVLA is betraying drivers who had entrusted it with their information.”

Paul Watters, head of roads policy at the AA, said: “The DVLA is aiding and abetting a dubious and sometimes downright scandalous parking ticket scam in private car parks and on private land. It is time for all parking enforcement on private land, which has become a goldmine for unscrupulous companies, to be properly regulated with full independent rights of appeal for the public who frequently fall victim to malpractice.”

A DVLA spokesman said: “We encourage anyone who believes their data has been misused to report it through our complaints procedure to inform our handling of future queries. We keep our processes under constant review to ensure they remain robust.”

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