James J. Yee, a former Muslim chaplain at the Guantánamo Bay detention center, says in a new book that military authorities knowingly created an atmosphere in which guards would feel free to abuse prisoners.

Mr. Yee, 37, is a former Army captain and a West Point graduate who was arrested and imprisoned in 2003 on suspicion of espionage. It was a case that, in the end, proved groundless, to the embarrassment of the Pentagon.

Mr. Yee was ultimately deemed guilty of minor administrative charges involving adultery and the presence of pornography on his computer, and given an honorable discharge. But those convictions, too, were later dropped.

The book, "For God and Country: Faith and Patriotism Under Fire," offers Mr. Yee's first public comments on what occurred at the camp while he was there.