The RAC wants to see tighter regulation of private clampers
The clamping of cars by private companies in England and Wales is legally shaky and could breach human rights, the RAC Foundation has claimed.
It says sometimes "exorbitant" fines are demanded without legal process and it wants to see laws changed.
Clamping cars also prevents drivers from putting right the obstruction they caused, the motoring body argues.
The Home Office is carrying out a consultation and intends to tighten the regulations governing private clampers.
Private clampers are separate from the council parking attendants who look after on-street parking and public car parks.
They have the right, on behalf of the landowner, to clamp a vehicle and charge the owner for the clamp to be removed.
I know of cowboys who put four clamps on a car and then charge £200 for each one to be removed
Craig Reade Approved Parking Services
The current regulations require signs to be prominently displayed to warn drivers.
Individual clampers also have to be registered with the Security Industry Authority in England and Wales. Clamping is outlawed in Scotland.
The Home Office consultation proposes a new system of regulation under which both individual clampers and their company have to be accredited and vetted.
They would have to introduce an appeals procedure for drivers who believe they have been unfairly treated.
But in the RAC Foundation's report, barrister Dr Chris Elliot says clamping by such companies could breach human rights.
"The Home Office is proposing a new licensing regime for private clampers but it is arguable that, if the release fee is unreasonable, their actions are incompatible with the Human Rights Act 1998, which demands that punishment should only come after a proper legal process."
"The purpose of clamping is to prevent a vehicle being removed from land it should not be on," he says. "It causes the harm to the landowner to persist. It is in effect, a 'self-inflicted wound'".
The RAC wants someone to challenge the law in court, or for the government to set out new legislation to legitimise clamping.
Currently, some companies stick to the rules and keep the fee they demand for removing the clamp within guidelines issued by the British Parking Association.
But the industry has a major problem with "cowboy clampers".
In one case, 18-year-old Emily Ritson found her car had disappeared nine minutes after a parking ticket expired at 10 o'clock at night. The police told her it had probably been removed by a clamping company.
Her father, Nigel, told the BBC: "I was really upset and angry because she's only 18 and she was 80 miles from home."
"I suspect they just towed the car away the second the ticket had expired."
After he was asked to pay £390 pounds to get it back, his response was: "You've got to be kidding. She was only nine minutes late."
Emily had to be rescued by a distant relative because the company would not return her car until the morning.
Mr Ritson said: "The man on the other end of the phone just said 'That's not my problem' and put the phone down on me."
Mr Ritson later won compensation in court.
But there are legitimate operations which stay within the current, fairly loose rules.
Approved Parking Services, in Maidstone, Kent, told the BBC it was a licensed clamper that charges £125 to remove a clamp.
But the company claimed other companies worked without proper accreditation.
Craig Reade, the company's managing director, said: "I know of cowboys who put four clamps on a car and then charge £200 for each one to be removed.
"Some of these vehicles aren't even clamped. They're being towed away and charged stupid money to get them back."
Mr Reade said he was regularly approached by local landowners wanting their land patrolled. His company provides the service for free, but keeps all the proceeds from the fines.
However, motorists are not afraid to fight back.
Experienced clamper Clive Woodend said he had years of abuse from motorists.
"I've been kicked, punched, threatened with being stabbed and all sorts. People don't like to accept being clamped."
Clamper Clive Woodend: ''I have been kicked and punched''
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