James Yee, a Muslim and a former Army chaplain who served at Guantánamo Bay, has a new book coming out this week in which he claims that Maj. Gen. Geoffrey D. Miller, the commander of the military detention center, regularly incited guards to abuse prisoners. Yee also says in the book that he regularly heard accounts of detainees being abused during interrogation sessions. The Department of Defense continues to insist that cases of abuse at Guantánamo were isolated occurrences.