Captain Duncan joined the Lancaster County Sheriff’s Office in 1995, was promoted to Sergeant in 1999 and promoted to Captain in 2001. During his service at the Sheriff’s Office, he has been assigned to Patrol, Criminal, Administrative Support, Civil, Narcotics Unit and has served as the Personnel and Training Deputy.

Captain Duncan graduated from Newport Harbor High School in Southern California in 1984 and received a Bachelors Degree in Business from Doane College in 2002.