SALT LAKE CITY -- Utah prisoners can read violence-laced literature such as "Games of Thrones" but are barred from accessing two guidebooks on manipulation.

Robert Greene's "The 48 Laws of Power" and "The Art of Seduction" are the only two books specifically banned at Utah State Prison's five libraries, the Salt Lake Tribune reported.

Prison officials were concerned they could instruct inmates how to negatively manipulate people, librarian Christie Jensen said.

Other states' prisons have far longer lists of banned books.

For example, the Texas Department of Criminal Justice prohibits more than 15,000 titles, including a biography of Oprah Winfrey and a collection of Shakespeare's love sonnets, according to Texas Civil Rights Project report.

Anna Brower Thomas of the Utah American Civil Liberties Union called the prison's ban on the two titles arbitrary.

"People can learn how to manipulate other people through all sorts of different sources. What is it about these two books that is so dangerous?" she said.

Also banned are 46 magazines dubbed sexually explicit, including Playboy and Hustler.