I used to be a Correctional Officer in a Max Security Prison for some years and those guys get big.
I also was the Kitchen officer so I know that they don't put **** in the food. Basic high school type slop. The food is high in calories and they have the opportunity to purchase commisary items and most of them are the kinds of food that would help you pack on weight. Add in the fact that you have gym time and yard time where you can lift and or run, it is not that hard to imagine.
Also, a smoke (no tobacco allowed in my states prison system) costs $20 in the prison black market. Weed $100 for a cap (chap stick cap full), so I can't even imagine what d-bol would go for. I never ran across any steroids in the prison system. Only drugs or tobacco. That doesn't mean it's not there. But the fact that easly obtained items like weed or tobacco are worth so much in the prison, I find it a little hard to believe that someone would go through all the trouble to smuggle steroids in. Because after all someone has to bring it in, usually prison staff, and they can make a lot more smuggling weed and tobacco rather than AAS.
MGeorge