Maryland Criminal Procedure Section 10-106

      (a)      In this section, "delinquency petition" means a petition filed under § 3-8A-10 of the Courts Article alleging that a child is a delinquent child.

      (b)      A person may file a petition for expungement of a criminal charge transferred to the juvenile court under § 4-202 of this article:

            (1)      after the date of the decision not to file a delinquency petition; or

            (2)      after the decision on the delinquency petition of facts-not-sustained.

      (c)      The court may grant a petition for expungement to a person when the person becomes 21 years old, if a charge transferred under § 4-202 of this article resulted in the adjudication of the person as a delinquent child.

      (d)      A court shall grant a petition for expungement of a criminal charge that was transferred to the juvenile court under § 4-202 of this article, if:

            (1)      the charge that was transferred under § 4-202 of this article did not result in the filing of a delinquency petition; or

            (2)      the decision on the delinquency petition was that there was a finding of facts-not-sustained.