Death Investigation of Incarcerated Individual in St. Mary’s County Ongoing

September 18, 2023
John Sherman Greenwell Jr., age 40 of no fixed address

John Sherman Greenwell Jr., age 40 of no fixed address

On Monday, September 11, 2023, John Sherman Greenwell, 44, an incarcerated individual of the St. Mary’s County Detention and Rehabilitation Center (SMCDRC) in Leonardtown, Maryland, was transported to MedStar St. Mary’s Hospital, where he was admitted.

Mr. Greenwell was treated and medically discharged on Friday, September 15, 2023, and returned to custody.

Following his return to the SMCDRC, Mr. Greenwell experienced a second medical emergency; he was evaluated by onsite medical staff, transported to MedStar St. Mary’s Hospital, and was later pronounced deceased.

In accordance with St. Mary’s County Sheriff’s Office policy, the Criminal Investigations Division is actively investigating the cause of death. Additionally, the Office of Professional Responsibilities is conducting an administrative investigation to determine if policies and procedures were followed by Sheriff’s Office personnel prior to and immediately following Mr. Greenwell’s death.

On Tuesday, December 29, 2020., Deputy First Class Carl Ball, along with Deputy Dylan Glenn, (currently in the field training process), were conducting a theft investigation at Big Lots, located in Lexington Park. Deputies were attempting to identify the suspect, later confirmed to be John Sherman Greenwell, age 41, of Lexington Park, in order to issue a criminal citation charging Greenwell with theft.

During the investigation, Greenwell suddenly attacked with a large knife he had concealed inside his coat. Greenwell stabbed/slashed DFC Ball on the hand, and Deputy Glenn confronted Greenwell and a physical confrontation ensued where Greenwell also attempted to stab Dep. Glenn.

During the confrontation Dep. Glenn went to the ground at which point Greenwell advanced above him with the knife raised. DFC Ball then fired his handgun, striking Greenwell in the right arm. DFC Ball sustained a significant laceration to his left hand and both Ball and Greenwell were transported via helicopter to area trauma centers for treatment. Dep. Glenn was not injured during the incident.