Sergeant First Class Lilley was a member of Battery B, 57th Field Artillery Battalion, 7th Infantry Division. He was seriously wounded by the enemy near Hagaru, North Korea, on 6 December 1950 and died of those wounds the following day. His remains were not recovered. His name is inscribed on the Courts of the Missing at the Honolulu Memorial.

For his leadership and valor, Sergeant First Class Lilley was awarded the Silver Star Medal, the Purple Heart, the Korean Service Medal, the United Nations Service Medal, the National Defense Service Medal, the Korean Presidential Unit Citation and the Republic of Korea War Service Medal.