Maryland Criminal Procedure Section 7-103

      (a)      For each trial or sentence, a person may file only one petition for relief under this title.

      (b)      (1)      Unless extraordinary cause is shown, in a case in which a sentence of death has not been imposed, a petition under this subtitle may not be filed more than 10 years after the sentence was imposed.

            (2)      In a case in which a sentence of death has been imposed, Subtitle 2 of this title governs the time of filing a petition.