Md. Code, Correctional Services § 11–1011

On written request, a correctional officer may have expunged from any file the record of a formal complaint made against the correctional officer if:

(1) (i) the internal investigation unit that investigated the complaint:

1. exonerated the correctional officer of all charges in the complaint; or

2. determined that the charges were unsustained or unfounded; or

(ii) a hearing board acquitted the correctional officer, dismissed the action, or made a finding of not guilty; and

(2) at least 3 years have passed since the final disposition by the correctional facility or hearing board.