Oz is a great series, one of televisions underrated shows. It has a certain relationship to soap opera in that something evil is always happening, and it is the unfolding of each instance of evil that fascinates. From my discussions with people who are actually in prison, it rings true. Every interaction has some machination working in the background. Behind every action, there lies a scheme, a plot to do someone else in. I like this series so much that it is one of the few TV shows I have bought completely, on DVD.
And, yes, I agree with the writer before me who commented that there are elements of satire in it. The character in the wheelchair who offers his jaundiced view of life does so with a certain bit of ironic humor.