Md. Code, Criminal Procedure § 2-102

(a) This section does not apply to an employee of the Department of State Police to whom the Secretary of State Police assigns the powers contained in § 2-412 of the Public Safety Article.

(b) (1) Subject to the limitations of paragraph (3) of this subsection, a police officer may make arrests, conduct investigations, and otherwise enforce the laws of the State throughout the State without limitations as to jurisdiction.

(2) This section does not authorize a police officer who acts under the authority granted by this section to enforce the Maryland Vehicle Law beyond the police officer’s sworn jurisdiction, unless the officer is acting under a mutual aid agreement authorized under § 2-105 of this subtitle.

(3) A police officer may exercise the powers granted by this section when:

(i) 1. the police officer is participating in a joint investigation with officials from another state, federal, or local law enforcement unit, at least one of which has local jurisdiction;

2. the police officer is rendering assistance to another police officer;

3. the police officer is acting at the request of a police officer or State Police officer; or

4. an emergency exists; and

(ii) the police officer is acting in accordance with regulations adopted by the police officer’s employing unit to carry out this section.

(4) The powers granted by this section are in addition to the powers granted by §§ 5-801, 5-802, 5-807, 5-808, and 5-901 of the Criminal Law Article and to the powers of fresh pursuit granted by Subtitle 3 of this title.

(c) (1) A police officer who acts under the authority granted by this section shall notify the following persons of an investigation or enforcement action:

(i) 1. the chief of police, if any, or chief’s designee, when in a municipal corporation;

2. the Police Commissioner or Police Commissioner’s designee, when in Baltimore City;

3. the chief of police or chief’s designee, when in a county with a county police department, except Baltimore City;

4. the sheriff or sheriff’s designee, when in a county without a county police department;

5. the Secretary of Natural Resources or Secretary’s designee, when on property owned, leased, operated by, or under the control of the Department of Natural Resources;

6. the chief of police of the Maryland Transportation Authority or chief’s designee, when on property owned, leased, operated by, or under the control of the Maryland Transportation Authority, Maryland Aviation Administration, or Maryland Port Administration;

7. the chief of police of the Department of General Services or the chief’s designee, when on property owned, leased, operated, managed, patrolled by, or under the control of the Department of General Services; or

8. the chief of police of the Maryland-National Capital Park and Planning Commission for the county in which the property is located, when on property owned, leased, or operated by or under the control of the Maryland-National Capital Park and Planning Commission; and

(ii) the Department of State Police barrack commander or commander’s designee, unless there is an agreement otherwise with the Department of State Police.

(2) When the police officer participates in a joint investigation with officials from another state, federal, or local law enforcement unit, the police officer shall give the notice required under paragraph (1) of this subsection reasonably in advance.

(d) A police officer who acts under the authority granted by this section:

(1) has all the immunities from liability and exemptions as a State Police officer in addition to any other immunities and exemptions to which the police officer is otherwise entitled; and

(2) remains at all times and for all purposes an employee of the employing unit.
agraph (1) of this subsection reasonably in advance.

(d) A police officer who acts under the authority granted by this section:

(1) has all the immunities from liability and exemptions as a State Police officer in addition to any other immunities and exemptions to which the police officer is otherwise entitled; and

(2) remains at all times and for all purposes an employee of the employing unit.

(e) (1) This section does not impair a right of arrest otherwise existing under the Code.

(2) This section does not deprive a person of the right to receive a citation for a traffic violation as provided in the Maryland Vehicle Law or a criminal violation as provided by law or the Maryland Rules.