Maryland Code, Courts and Judicial Proceedings § 10-4B-05

(a) Upon the request of an investigative or law enforcement officer of a law enforcement agency authorized to install and use a pen register under this subtitle, a provider of wire or electronic communication service, landlord, custodian, or other person shall furnish the investigative or law enforcement officer with all information, facilities, and technical assistance necessary to accomplish the installation of the pen register unobtrusively and with a minimum of interference with the services that the person ordered by the court accords the party with respect to whom the installation and use is to take place, if such assistance is directed by a court order under § 10-4B-04(b)(5) of this subtitle.

(b) Upon the request of an officer of a law enforcement agency authorized to receive the results of a trap and trace device under this subtitle, a provider of a wire or electronic communication service, landlord, custodian, or other person shall install the device on the appropriate line and shall furnish the investigative or law enforcement officer all additional information, facilities and technical assistance including installation and operation of the device unobtrusively and with a minimum of interference with the services that the person ordered by the court accords the party with respect to whom the installation and use is to take place, if the installation and assistance is directed by a court order under § 10-4B-04(b)(5) of this subtitle. Unless otherwise ordered by the court, the results of the trap and trace device shall be furnished to the officer of a law enforcement agency, designated in the court order, at reasonable intervals during regular business hours for the duration of the order.

(c) A provider of a wire or electronic communication service, landlord, custodian, or other person who furnishes facilities or technical assistance under this section shall be compensated for reasonable expenses incurred in providing the facilities and assistance.

(d) Nothing in this subtitle may be construed as creating a cause of action against any provider of a wire or electronic communication service, its officers, employees, agents, or other specified persons for providing information, facilities, or assistance in accordance with the terms of a court order under §§ 10-4B-02 through 10-4B-05 of this subtitle.

(e) A good faith reliance on a court order, a legislative authorization, or a statutory authorization is a complete defense against any civil or criminal action brought under §§ 10-4B-02 through 10-4B-05 of this subtitle or under any other law.