Oakwood and Drake Hall inmates working in prison call centres
Convicted criminals in the West Midlands are being paid to work in call centres inside their prisons.
Inmates at HMP Oakwood, near Wolverhampton, and Drake Hall, in Staffordshire, carry out market research for insurance companies.
The Centre for Crime Prevention said the project was "incredibly naive".
But the Ministry of Justice said it was a pilot scheme which may be rolled out further if it is successful, and added the prisoners have risk assessments.
A spokeswoman for the Ministry of Justice said: "We do not want prisoners sitting idle in their cells when they should be working towards their rehabilitation.
"We prepare offenders for work inside prison so they can get a job after release - this reduces the chances that they will reoffend in the future, meaning lower crime and fewer victims.
"All prisoners working in call centres are risk-assessed and stringent security measures are in place, with calls supervised and recorded."
She said the small pilots are being monitored and would only be increased to other prisons if they were deemed successful.
She added the workers cannot see sensitive information about the people they are calling, such as addresses.
The phone numbers of customers are also protected as all calls are routed through a computer.
"At no point can they ask the value of items, record data outside of the secure systems or deviate from a carefully-worded script," she added.
The spokeswoman could not say whether any other prisons have similar schemes, nor which companies run the ones mentioned above.
She confirmed the work is taking place within the confines of the prisons.
On their websites, both facilities say work opportunities are available for inmates.
Alex Hewson from the Prison Reform Trust said they supported the scheme.
"We encourage this type of scheme because it develops skills that may prove to be useful for the workplace generally, and gives prisoners a greater chance of getting employment on release," he said.
"I can understand why there may be concerns but the scheme is risk-assessed and I think it's really important those people get opportunities to help them resettle."
A statement from G4S, which runs HMP Oakwood prison, said: "The call centre at HMP Oakwood is one of many partnerships we run with businesses, and enables prisoners to work towards apprenticeships and industry-recognised qualifications.
"All the prisoners are carefully security checked and interviewed before working in the centre, calls are made remotely by computer, and every conversation is closely monitored by supervisors. No information from the calls is stored and there is no way any personal information can be used for any criminal purposes."
Oakwood is a male prison and Drake Hall is for female offenders.