Lt. Colonel Doyle began his career with the St. Louis County Police on April 27, 1992 when he was hired as a Probationary Police Officer and assigned to the South County Precinct. As a member of the St. Louis County Police Department, he has served in the following capacities:
- Officer - South County Precinct, North County Precinct and Community Action Team
- Detective - Bureau of Drug Enforcement, FBI Gang Task Force, Intelligence Unit and FBI Public Corruption Task Force
- Sergeant - North County Precinct and the Neighborhood Policing Unit
- Lieutenant - North County Precinct and South County Precinct
- Lieutenant - Interim Police Chief and then Commander: City of Jennings Detail
- Captain - Commander of the North County Precinct and then Commander of the Division of Criminal Investigation
Lt. Colonel Doyle was promoted to his current rank and assigned to his current position as Commanding Officer of the Division of Patrol in September 2014.
Lt. Colonel Doyle is an avid supporter of police and community relations, and is currently involved in a number of community oriented programs. Lt. Colonel Doyle serves on numerous governing boards including the St. Louis Chapter of the National Organization of Black Law Enforcement Executives were he currently serves as President. Lt. Colonel Doyle is also the founder of the St. Louis County Police Department Police Athletic League (PAL). He received his Bachelors in Criminal Justice from Lindenwood University. Lt. Colonel Doyle has also attended countless hours of training in a variety of law enforcement, leadership and management related areas. He is a graduate of the 245th session of the FBI National Academy. Lt. Colonel Doyle is the recipient of numerous letters of appreciation, Awards of Excellence, and Chief's Commendations.