Colonel McCann was raised in Columbus, Mississippi. He was commissioned a Marine Officer from the U.S. Military Academy in May 1992 and subsequently attended the USMC Basic School and Infantry Officer Course. Colonel McCann was then assigned to 3d Battalion, 2nd Marines, 2nd Marine Division where he served as a rifle platoon commander and company executive officer. During that time he deployed with 26 MEU (SOC) and participated in Operation Restore Hope in Somalia.
Colonel McCann was next assigned as the Officer Selection Officer for Recruiting Station Albuquerque, New Mexico. During that time he was selected as the Officer Selection Officer of the Year for 1996. At the completion of this tour, Colonel McCann applied and was selected for the Excess Leave Program (Law). He then attended the University of Mississippi School of Law where he served as the Editor of the Journal of National Security Law and was awarded his Juris Doctor in May 2001.
Following law school, Colonel McCann was assigned to the Legal Service Center, Marine Corps Base Hawaii where he served as Defense Counsel, Senior Defense Counsel and Deputy Staff Judge Advocate. During 2004, he was assigned to 1st Marine Division in support of OIF II and served as the Detention Operations Officer for the Division, charged with establishing all detention facilities, drafting all detention SOPs, and establishing detention standards for Marine forces in theater. He was also tasked with vetting all detainees nominated for release from Abu Gharib prison as well as planning and conducting the actual detainee releases in Ramadi and Fallujah.
Colonel McCann was next assigned as Deputy Staff Judge Advocate, 3rd Marine Aircraft Wing. During this assignment, he deployed to Al Asad, Iraq as the SJA for 3d MAW (FWD) from February 2006 until February 2007 and was responsible for all legal support to Marine air operations in theater. He then applied and was accepted for the Special Education Program where he obtained an LL.M. in International Law (honor graduate) from the University of San Diego.
Upon completion of the SEP program, Colonel McCann was assigned as the Branch Head, Operational Law (JAO), Judge Advocate Division, Headquarters Marine Corps. During that tour he was selected to participate in the MIT Seminar XXI International Affairs and National Security Program. He was then chosen to join Chairman’s Legal Counsel where his portfolio included the law of armed conflict, detention operations, and arms control agreements. During this assignment, he frequently traveled to Afghanistan in support of Special Operations detention operations and worked extensively with DoD General Counsel’s office as a member of the U.S. Delegation representing the U.S. at international meetings of the Convention on Certain Conventional Weapons (CCW) in Geneva, Switzerland.
Colonel McCann was then selected for command and reported to Marine Corps Recruit Depot, San Diego in June 2010 to assume duties as Commanding Officer, 1st Recruit Training Battalion. Upon completion of command, he was assigned to be the Staff Judge Advocate, Marine Corps Base Hawaii where he was the senior legal advisor for all Marine Corps installation matters in Hawaii and the mid-Pacific region. Following completion of that tour, Colonel McCann was assigned the Officer in Charge, Legal Services Support Section, National Capital Region, Quantico, VA and was responsible for supervising all classified and high visibility court martial prosecutions in the Marine Corps. Colonel McCann was then assigned as the Staff Judge Advocate, Marine Corps Forces Pacific in September 2015. He assumed his current duties as Staff Judge Advocate, U.S. Indo-Pacific Command in July 2018.