Maryland Code, Courts and Judicial Proceedings § 9-203

(a) In any criminal proceeding in which a warrant is issued for the purpose of requiring the attendance of a person as a material witness for the State, the witness must be taken promptly before a District Court commissioner before he is committed to jail.

(b) If the commissioner determines, after a hearing, that the person brought before him should be held as a witness for the State, he shall set a reasonable bond for the appearance of the witness in the criminal proceedings when required.

(c) If the witness is unable to post the bond set by the commissioner he shall be committed to jail until he posts the bond.

(d) Upon the commitment to jail of a witness, the commissioner shall notify immediately the State's Attorney of the county where the witness is being held. The sheriff, warden, or other custodian of the jail in which the witness is held shall also notify immediately the State's Attorney.

(e) Unless the State's Attorney makes application in writing prior to the expiration of seven calendar days from the date of commitment of the witness to a judge of the circuit court of the county where the witness is committed for authority to continue to hold the witness, the sheriff, warden, or other custodian of the jail shall immediately upon the expiration of seven days release the witness.

(f) The filing of a petition for authority to continue to hold a witness longer than seven days may be granted by a judge, only upon the conditions and in accordance with the procedure provided by the Maryland Rules.

(g) The State's Attorney may order the release of the witness from custody at any time before or after the expiration of seven days by placing an endorsement to that effect on the commitment or warrant.

(h) A confined witness shall be paid $10 per day for each day confined in addition to the witness fees payable pursuant to § 9-202. Payment shall be made by the county in which the prosecution of the case is carried on.