Maryland Transportation Section 22-201.2
§ 22-201.2.
  (a)   Notwithstanding any other provision of this subtitle, if a driver of a vehicle on a highway operates the vehicle's windshield wipers for a continuous period of time because of impaired visibility resulting from unfavorable atmospheric conditions, the driver shall light the vehicle's headlamps or fog lights.
  (b)   A violation of this section is not considered a moving violation for purposes of § 16-402 of this article.
  (c)   (1)   If a person is convicted under this section, the conviction may not:
      (i)   Be considered evidence of negligence;
      (ii)   Be considered evidence of contributory negligence;
      (iii)   Limit liability of a party or an insurer; or
      (iv)   Diminish recovery for damages arising out of the ownership, maintenance, or operation of a motor vehicle.
    (2)   Subject to the provisions of paragraph (3) of this subsection, a party, witness, or counsel may not make reference to a violation of this section.
    (3)   Nothing contained in this subsection may be construed to prohibit the right of a person to institute a civil action for damages against a dealer, manufacturer, distributor, factory branch, or other appropriate entity arising out of an incident that involves a defectively installed or defectively operating headlamp or fog light.
  (d)   A person who is convicted of a violation of subsection (a) of this section is subject to a fine not to exceed $25.
  (e)   A police officer may enforce the provisions of this section only as a secondary action when the police officer detains a driver of a motor vehicle for a suspected violation of another provision of the Code.