Security requirements push up costs, according to BT
An official complaint about telephone calls from prison costing seven times normal payphone rates has been made by the National Consumer Council (NCC).
The group says that half the calls made from jail last less than three minutes because of the high costs involved.
It has made a super-complaint about the issue to regulator Ofcom.
But provider BT says pricing is unusual owing to security and the government argues that cutting the cost would need a public subsidy.
The NCC, which covers England, and its counterparts in Scotland and Wales, as well as the Prison Reform Trust, say that the cost of calls "appear unrelated to the cost of provision".
The NCC says for calls to landlines, there is a minimum charge of 10p for the first 55 seconds, then a charge of 1p per 5.5 seconds (or part thereof).
It says: "This is equivalent to 11 pence per minute. This does not vary by time of day or destination of the call."
They are also questioning why costs remain high while costs of other basic telephone services have fallen by 60%. A 30-minute call costs at least seven times as much as from a payphone, they say.
They add that the terms of existing services seek to prevent competition and contracts are "shrouded in secrecy".
"We are extremely concerned by the nature of this market. Just because the consumers are prisoners it does not mean they should be exploited and pay well over the odds for telephone calls," said Philip Cullum, NCC acting chief executive.
The groups point to research that says that almost half prisoners lose contact with their families during their sentence. Prisoners are six times less likely to offend if they have a supportive family network.
Prison overcrowding means more movement around prisons and fewer opportunities for families to visit, the groups say.
"If prisoners lose contact with their families while inside, the cost to society could be far greater than the price of a premium-rate phone call," said Liberal Democrat justice spokesman David Howarth.
"The support of loved ones is a crucial factor in helping to prevent re-offending on release. There are serious questions about the necessity of these phone charges and who keeps the revenue."
Phone services are provided by BT in England and Wales and Siemens in Scotland.
Studies suggest almost half of all inmates lose contact with their families
A BT spokesman said pricing was set in agreement with the Prison Service.
"The service is not comparable to any other payphone service as it requires a great deal of investment in security and monitoring which is essential to the specific requirements of HMPS," he said.
Prisons minister Maria Eagle said she was "disappointed" that the NCC had brought the complaint.
"Prices are benchmarked against market conditions. To reduce costs under the current contract would require a large subsidy at public expense," she said.
She added that the current contract would end in 2011 with the next tendering process starting later this year.
Ofcom has 90 days to respond to the super-complaint, which calls for the publication of the contracts and independent analysis of the relationship between the charges and the costs of providing the services.
Relatively few super-complaints have been made since the system was introduced in recent years. They have included complaints about bank charges, payment protection insurance and doorstep lending.