The way that Steve feels about jail is an important part of the book and the overall character development of Steve Harmon. Steve is terrified of jail. The place itself scares him, and the people in jail scare him even more. As readers discover more and more of Steve's aversion to jail, the more they may feel convinced that Steve is not guilty. He simply is not like the other people in jail. Steve is not violent like the other inmates, and he does not talk about the sex and violence the way that everybody else in jail seems to do.
The reason that this information is important is because it helps show readers that Steve is not the monster that the prosecuting attorney is trying to make him out as. Steve does question the validity of whether or not he is a monster, but his reaction to jail and the other inmates shows readers that he does not belong there. What is still unknown is whether or not Steve is actually guilty of the crime. Most readers probably feel confident in saying that Steve is not a monster; however, most readers probably finish the book not knowing exactly whether or not Steve is indeed guilty, on some level, of the murder.