By Geoff Adams-Spink
Age & disability correspondent, BBC News website
According to the Local Government Association, half of the blue badges in London are being abused. What needs to be done to restore the credibility of a scheme that was originally designed to make life easier for disabled people?
Blue badges are changing hands among criminals
When the Barnetts - from Ilford in Essex - emerged from hospital to return to their car, they had to walk through shattered glass scattered all over the pavement.
They feared the worst and the worst was what they found: their car window had been smashed so Dianah Barnett's blue badge could be stolen.
"When we came out we realised that all the other cars had been broken into, all for their blue badges - there must have been eight or nine cars in a row," she recalls.
The badge has now been stolen twice and the Barnetts have to visit the hospital once or twice a week, often for the whole day.
They no longer take any chances: they either pay £3.50 an hour in the car park or Martin Barnett sits in the car with the blue badge.
With the cost of parking escalating and London's congestion charge at £8.00 a day, disabled parking badges are now a valuable commodity.
They can change hands for as much as £1600 on the black market, according to police and local government sources.
Residents who live close to Arsenal's new Emirates Stadium, in north London, say that, on match days, their streets are full of vehicles displaying blue badges from which emerges a group of fit young men off to see the match.
Gary Griffiths heads a team of parking enforcement officers who make it their business to identify offenders.
Islington Council estimates that as many as 400 extra blue badges appear on the streets when Arsenal are at home.
Griffiths and his team approach a stocky, white-haired man who they suspect is using a badge illegally.
Griffiths and his team approach a stocky, white-haired man
His badge was issued by Camden Council but he gives an address several miles away in Romford, Essex.
He is unable to explain why his badge was not issued by his local council and a police officer is called to interview him.
Later he told us his badge was "legitimate, but not mine".
Asked whether what he is doing amounts to fraud, he says that he supposes that it is.
And when pressed as to whether he is behaving fairly, he replies:
"No, not really I suppose."
Islington Council is using new powers available in England since September last year giving parking attendants the right to inspect disabled parking badges.
Previously, only a police officer was able to do so.
Although the badges include a picture of the holder, when it is displayed in the windscreen, the photograph is face down.
But very few authorities are using this new tool to clamp down on fraud as much as Islington.
The Five Live report asked all of the London boroughs and several other large cities whether they were inspecting blue badges.
Of the 40 local authorities contacted, 12 replied.
Just under a half said the power was not being used at all.
Others said they did not keep records about blue badge inspection - though this does not necessarily mean they are not doing so.
The City of London said it would not start to carry out inspections until staff had received appropriate training.
And the London Borough of Newham knows about the new powers but chooses not to use them as they wish to avoid confrontation with the public.
The government says that it has made the new powers available - something it describes as "key changes to tackle abuse of blue badges".
"Updated guidance for local authorities, which will remind them of their blue badge enforcement powers, will shortly be available," a spokesperson said.
One expert told us that a blue badge would save the holder, on average, £5,000 a year if they parked in a city centre every day for work.
With the price of parking continuing to rise and London's congestion charge zone about to be extended, criminals are likely to continue to regard the blue badge as hot property.
Five Live Report: Parking Blues can be heard on Sunday 18 February at 1100 GMT and will also be available at the Five Live Report website.