If you would expect ANY book to be banned, you would expect it of this one. Violent sex, senseless acts of violence, rape, a sociopaths view of society - and of society hitting back, and a lack of respect for religion. All these themes would get this book to the top of the banned books list. And so it appears to be in many references on the internet.
One interesting note is that the book has 21 chapters, but was originally printed in the United States with only 20. Very strange, considering that the 21st chapter is the ONE chapter that is NOT violent, but instead, contemplative and filled with a final moral. Why would they print it without this chapter - god knows.
And once again, this seems to be a book where the MOVIE was banned more than the book.
The only specific instances of this book being banned are as follows:
In 1973 a book seller in Orem, Utah, was arrested to selling the novel. Charges were later dropped, but the book seller as forced to close the store and relocate to another city.
Removed from Aurora, Colo. high school (1976) due to "objectionable" language and from high school classrooms in Westport, Mass. (1977) because of "objectionable" language.
Removed from two Anniston, Ala. High school libraries (1982), but later reinstated on a restricted basis. Source: 2004 Banned Books Resource Guide, ed. Robert P. Doyle.