This is so bizarre, I didn't think it would be possible in this day and age. There are prisons in the US where inmates are only allowed to read the Bible, and nothing else! The ACLU is filing a lawsuit. Here is some of the text explaining the situation a bit better and links to a petition you can sign on behalf of the prisoners. I honestly think that being forbidden from reading any book but Bibles is a form of cruel and unusual punishment.
"Our inmates are only allowed to receive soft back bibles in the mail directly from the publisher," First Sergeant K. Habersham wrote in an a July 12 e-mail to the editor of Prison Legal News, which provides prisoners across the country with publications explaining their legal rights. "They are not allowed to have magazines, newspapers, or any other type of books."
In fact, according to the prison's formal policy, outside of the Bible, inmates are allowed to receive "letters only," as well as up to three pictures, but -- strangely, and unfortunately for shareholders of the struggling electronics company -- "they cannot be Polaroid." And since the prison doesn't even have a library, that means detainees are more or less stuck re-reading their favorite parts of Leviticus day in and day out.