I'm so stressed by the way I've been treated," the prisoner began, "that I've started smoking heroin again."

I asked him politely where he was getting it. "It's everywhere," he replied. "I handed over toiletries I bought from the canteen [prisoners can order from an in-prison shop] and he gave it to me. I know I'm getting addicted. My drug of choice on the outside was crack cocaine. I'd never done heroin until I came in here. I started taking it when I found that my personal papers had been given to the wrong person. It's the prison's fault and an abuse of my human rights."

He added, inevitably, "I want compensation". He'll probably get it.

His situation is not an isolated one. In my regular working trips to and from a B-category London prison, I see how inefficiency, supplies of class A drugs and prisoners who know how to play the system are an intrinsic part of prison life today.