Maryland Code, Criminal Procedure § 10-102

(b)(1) A court record or a police record that existed before July 1, 1975, and is still maintained, may be expunged under this subtitle.

(2) A person who is entitled to the expungement of a court record or a police record that existed before July 1, 1975, may use the procedures for expungement provided under this subtitle.

(3) The limitation periods provided in § 10-105 of this subtitle begin when the person becomes entitled to expungement of a court record or a police record that existed before July 1, 1975.

(4) The custodian of court records or police records that were made before July 1, 1975, and that may be expunged under this subtitle:

(1) a record about a minor traffic violation;

(2) the published opinion of a court;

(3) a cash receipt or disbursement record that is necessary for audit purposes;

(4) a transcript of court proceedings made by a court reporter in a multiple defendant case;

(5) an investigatory file; or

(6) a record of the work product of a law enforcement unit that is used solely for police investigation.