Mary Ann Thompson Promoted to Warden of St. Mary’s County Detention and Rehabilitation Center

April 8, 2022

Sheriff Tim Cameron and the men and women of the St. Mary’s County Sheriff’s Office congratulate Mary Ann Thompson for her promotion to Warden of the St. Mary’s County Detention and Rehabilitation Center. Serving as the facility’s Deputy Warden since January 2019, Thompson was promoted to Warden on April 1, 2022.

Major Deborah Diedrich who previously served as Warden retired at the end of February after serving with the Sheriff’s Office Corrections Division for more than 33 years.

Thompson worked for the FBI Washington Field Office Division for five years before joining the St. Mary’s County Sheriff’s Office in November 1989 in the Corrections Division. Thompson worked her way up through the division, working as a Corrections Coordinator, Executive Coordinator, Support Services Administrator, Deputy Warden and ultimately to Warden.

“I am looking forward to your leadership and tenure at the detention center for a long time to come,” Sheriff Cameron told Thompson this week.


“I am so very humbled Sheriff Cameron has entrusted me to be Warden of the St. Mary’s County Detention and Rehabilitation Center,” Thompson said. “I look forward to building upon the legacy of the Wardens who have gone before me advancing community corrections, and offender re-entry for our community.”

“I am truly touched to be selected as Warden; it is my dream job. I have always wanted to make a difference for our community through positively changing people’s lives not only the offenders entrusted to our care but the amazing personnel who work in the Corrections Division,” she said.

Since becoming Deputy Warden, major projects at the detention center included the construction and opening of a new addition to the facility, a new medical unit and new central control and security system upgrades. The Sheriff’s Office also partnered with the St. Mary’s County Health Department to procure an office module which now serves as the Community Corrections Center.

In four straight audit cycles, the St. Mary’s County Detention and Rehabilitation Center achieved 100-percent compliance from the Maryland Commission on Correctional Standards.

Thompson also serves on the Executive Board for the Middle Atlantic States Correctional Association.

Congratulations Mary Ann, we wish you the best in your new position.