Md. Code, Pub. Safety § 3-601

(a) (1) A law enforcement agency may not establish a mandatory waiting period before taking a missing person report. (2) A law enforcement agency shall make every effort to inform the general public and the family of a missing person that the agency does not impose a mandatory waiting period before taking a missing person report. (b) In accordance with subsection (a) of this section, a law enforcement agency: (1) shall accept without delay a report of a missing person provided in person; and (2) may accept a report of a missing person by phone or other electronic means if: (i) that form of reporting is consistent with the policy of the law enforcement agency; and (ii) the reporting person completes the report in person as soon as possible. (c) With regard to a missing person as defined in § 3–604 of this subtitle, a law enforcement agency shall enter all necessary and available information into the National Crime Information Center computer network within 2 hours after receipt of the minimum information necessary to make the entry.