RALEIGH, N.C.—North Carolina prison inmates can receive publications while incarcerated, but the reading material is highly regulated under what advocates say is a vague policy often enforced without explanation.

Department of Correction officials have banned magazines such as GQ and Cosmopolitan, and even self-help books, prisoner advocates say. One inmate recently sued the department because he couldn’t read magazines and newspapers about gay life.

“We have had many letters from prisoners complaining that magazines and other publications were being kept from them for what seem to be arbitrary reasons,” said J. Phillip Griffin, a lawyer with N.C. Prisoner Legal Services who is representing the inmate who filed the suit.

The state prison system’s policy allows mailroom staffers wide discretion to review reading material before giving it to prisoners, and the prison warden or superintendent records any decision to withhold a publication.

Joseph Urbaniak filed a lawsuit against corrections officials, saying his rights were violated when prison officials withheld several publications about gay life, including The Advocate and the New York Blade.