Sparks was born in La Rochelle, France,[2] was raised in Mount Holly, New Jersey[3] and enlisted in the U.S. Navy in July 1971.

From 1996 to 1998, he was Deputy Legal Advisor for the National Security Council, retiring from the Marine Corps at the end of this service in 1998.

From 1998 to 1999, he served as Special Assistant to the Secretary of Agriculture in which role he was instrumental in the settlement of a class action lawsuit against the department by African American farmers.

From 2000 to 2016, he served as Commissioner to the Chief Judge of the United States Court of Appeals for the Armed Forces.

[4] On July 30, 2015, President Obama nominated Sparks to serve as a United States Circuit Judge of the United States Court of Appeals for the Armed Forces, to the seat vacated by Judge James E. Baker, who took senior status on July 31, 2015.