He teaches at the Howard University School of Law and his is a 2013 winner of a Hugh M. Hefner First Amendment Award. He served as a judge advocate in the United States Air Force from October 1983 until he retired as a Colonel in October 2008. From September 2005 until October 2007, he was the Chief Prosecutor for the Military Commissions at Guantanamo Bay, Cuba. He led a multi-agency prosecution task force of more than 100 personnel from the Department of Defense, Department of Justice, Central Intelligence Agency, Federal Bureau of Investigation, and other federal agencies. For nearly two years he was one of the leading advocates for military commissions and the detention facility at Guantanamo Bay. He resigned as chief prosecutor in October 2007 because of his objection to the use of evidence obtained by torture and growing political interference in the military commissions, and he became a critic of the process he once defended.