For the last three weeks activists in Cardiff have been protesting outside a company which provides solar panels and has a call centre in Cardiff.
The company called Becoming Green has been using dozens of prisoners from Prescoed prison in Monmouthshire on "work experience" for at least two months at a rate of 40p an hour in the private company's telephone sales division in Cardiff.
People working in the prisons sector described the scheme as "disgusting" and a "worrying development."
The protesters fully appreciate the need for prisoners to be rehabilitated.
But we cannot understand why the rate for the job is so low. Surely they say if this is about getting prisoners ready for life on the outside, then the proper rate for the job should be paid.
Anything else is exploiting the prisoners while undermining the terms and conditions of the existing workforce.
Cardiff trades council says there are reasons for scepticism about the company's motives.
"We've been informed that Becoming Green has dismissed a large number of employees who, apparently, had 'performance issues'.
"It seems it has replaced those workers by bussing in prisoners from HMP Prescoed. We know of many unemployed people in Cardiff who have experience of call centre work and would jump at a chance to have a job and get off benefits - though obviously they wouldn't work for £3 a day."
The bussing of prisoners into Cardiff comes at a time when a restaurant is due to open in the former visitors centre in Cardiff Prison.
The restaurant - called Clink Cymru - at Cardiff Prison will be staffed by 30 prisoners from HMP Cardiff and Prescoed.
It will employ 24 chefs and waiters and four cleaners, giving prisoners the skills and qualifications required to work in the higher end of the hospitality industry.
Everything at the restaurant - from full meals to biscuits and bread - is made from scratch by the prisoners.
Even the tables, chairs and uniforms have been made by offenders, and the food is sourced from a prison farm at HMP Prescoed.
It all sounds great.
But the trades council points out: "We understand the need to rehabilitate offenders.
"But in the case of Clink Restaurant many of the goods made by prisoners for the project could have been made by Remploy workers.
"Indeed, it seems the government is intent on closing Remploy factories and putting the work into prisons so they only have to pay £3 a day in wages.
"What restaurant in Cardiff can compete with one that pays its staff such ridiculously low wages? This is just using cheap labour - it's exploitative and immoral."
Protesters in Cardiff are determined to step up their campaign and are seeking urgent talks with the local branch of the Prison Officers Association. Rehabilitation must not turn into prison labour - a cheap and exploitative alternative to real jobs which puts other workers out of work.
Ramon Corria is secretary of Cardiff trades council.
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