MD Pub Safety Code § 3-104 (2017) Subsection d, paragraph 2 Before an interrogation, the law enforcement officer under investigation shall be informed in writing of the nature of the investigation. (subsection L: 1) The law enforcement agency may order the law enforcement officer under investigation to submit to blood alcohol tests, blood, breath, or urine tests for controlled dangerous substances, polygraph examinations, or interrogations that specifically relate to the subject matter of the investigation. (2) If the law enforcement agency orders the law enforcement officer to submit to a test, examination, or interrogation described in paragraph (1) of this subsection and the law enforcement officer refuses to do so, the law enforcement agency may commence an action that may lead to a punitive measure as a result of the refusal. (3) If the law enforcement agency orders the law enforcement officer to submit to a test, examination, or interrogation described in paragraph (1) of this subsection, the results of the test, examination, or interrogation are not admissible or discoverable in a criminal proceeding against the law enforcement officer.

subsection m, paragraph 1: If the law enforcement agency orders the law enforcement officer to submit to a polygraph examination, the results of the polygraph examination may not be used as evidence in an administrative hearing unless the law enforcement agency and the law enforcement officer agree to the admission of the results. Subsection N:1 on completion of an investigation and at least 10 days before a hearing, the law enforcement officer under investigation shall be: notified of the name of each witness and of each charge and specification against the law enforcement officer

MD Pub Safety Code § 3-107 (2017)

Subsection A Right to hearing. --(1) Except as provided in paragraph (2) of this subsection and § 3-111 of this subtitle, if the investigation or interrogation of a law enforcement officer results in a recommendation of demotion, dismissal, transfer, loss of pay, reassignment, or similar action that is considered punitive, the law enforcement officer is entitled to a hearing on the issues by a hearing board before the law enforcement agency takes that action. Subsection C: Membership of hearing board. -- (1) Except as provided in paragraph (5) of this subsection and in § 3-111 of this subtitle, the hearing board authorized under this section shall consist of at least three voting members who: (i) are appointed by the chief and chosen from law enforcement officers within that law enforcement agency, or from law enforcement officers of another law enforcement agency with the approval of the chief of the other agency; and (ii) have had no part in the investigation or interrogation of the law enforcement officer. (2) At least one member of the hearing board shall be of the same rank as the law enforcement officer against whom the complaint is filed. (5) (i) 1. A law enforcement agency or the agency's superior governmental authority that has recognized and certified an exclusive collective bargaining representative may negotiate with the representative an alternative method of forming a hearing board. MD Pub Safety Code § 3-108 (2017) Subsection A (4) If the hearing board makes a finding of guilt, the hearing board shall:(i) reconvene the hearing; (ii) receive evidence; and (iii) consider the law enforcement officer's past job performance and other relevant information as factors before making recommendations to the chief. Subsection B Recommendation of penalty. --(1) After a disciplinary hearing and a finding of guilt, the hearing board may recommend the penalty it considers appropriate under the circumstances, including demotion, dismissal, transfer, loss of pay, reassignment, or other similar action that is considered punitive. Subsection D (3) The recommendation of a penalty by the hearing board is not binding on the chief. MD Pub Safety Code § 3-110 (2017) (a) In general. -- On written request, a law enforcement officer may have expunged from any file the record of a formal complaint made against the law enforcement officer if: (1) (i) the law enforcement agency that investigated the complaint: 1. exonerated the law enforcement officer of all charges in the complaint; or 2. determined that the charges were unsustained or unfounded; or (ii) a hearing board acquitted the law enforcement officer, dismissed the action, or made a finding of not guilty; and (2) at least 3 years have passed since the final disposition by the law enforcement agency or hearing board. (b) Admissibility of formal complaint. -- Evidence of a formal complaint against a law enforcement officer is not admissible in an administrative or judicial proceeding if the complaint resulted in an outcome listed in subsection (a)(1) of this section.