One Twix, one Bounty, one Mars bar, two teas, seven Cokes, three packets of Hula Hoops and a couple of packets of Jammie Dodgers. That’s pretty much the average order when serving tea at the prison-and that’s just tea for two! If the inmates are trying to get off the drugs that have often landed them here in the first place, they need a lot of sugar.

The atmosphere is quite relaxed. Different-coloured bibs mark out who’s on remand and who’s serving time. Ages are mixed, generally young. Some mothers are sanguine, others are tearful. There are plenty of children and young girlfriends. I’m helping Tina, who’s been doing this for a number of years and whose eyes are not nearly as wide open as mine. She compliments an Irish woman on the ringlets in her daughter’s hair. ‘I shave the babies’ heads-that’s what the Indians do, you know-we just trim an inch a year and my other daughter, she’s got beautiful hair down to here,’ she gestures below her waist, ‘but you’ve got to shave it.’ A man approaches the counter, clearly on his first visit. He looks stunned. ‘Are they allowed to take the food back to their cells with them?’ Absolutely not.

Two dog handlers come up and, after some small talk, ask if we would be stooges for one of the dogs, still in training. They would take us to a different room, place some drugs in our pockets and see if the dog finds them. I can’t imagine anything more terrifying, having instant Kafkaesque nightmares about being actually locked up or my jeans forever smelling so that I’ll be arrested next time I go through airport security. Tina volunteers and, when she returns, she says the dogs were frightening. Having found the drugs, they leap right up, level with your head, repeatedly.

The visitors are fairly patient while we supply their enormous orders, but they don’t want to waste time, the hour is precious. My maths is hopeless and they often do the adding-up for me. They’re polite and pleased to see you-the shop, which donated more than £7,000 last year to prisoner-related causes, isn’t always open.We get chatting to one of the prison guards on our way out, who says he’s increasingly demoralised. He thinks there will be full privatisation of the prison within a couple of years and that, after 15 years of service, he’ll be out of a job. He may be right. We have more privatised prisons than any other country in Europe at the moment, but although the Government is supporting privatisation of all other aspects (catering, maintenance, rehab-ilitation), it isn’t rushing towards privatising the staff.

The guard is probably paid more than his equivalent in the private sector and perhaps he hates change, but he also seems to be genuinely proud of his work. In the last few minutes of our shift, a visitor says she hasn’t seen me before-she’s clearly seen most volunteers over the years and I wonder how many more hours she’ll spend in this bland room. The visitors leave and the men sit patiently, waiting to be escorted back to their cells.

At the bus stop outside, an elderly woman who bought a lot of biscuits is sitting in the sun. She looks as if she’s on a regular day out-it’s what she does on Tuesdays and she’ll be back next week. For me, any time spent within these walls, wires and gates is fascinating, exhausting and throws up a multitude of emotions and questions. I couldn’t work there full-time, no matter how much I was paid. I don’t know whether the system will manage to marry the various skills between the public and private sectors, or which pair of volunteers will be unlocking the shop today, but I do know they’ll be selling a lot of Coca-Cola.

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