It is unlawful for any person to loiter about or remain at any public way, public place, or place open or legally accessible to the public within a certified drug-free zone, as herein provided, for the purpose of engaging in drug-related activity that is prohibited by any of the provisions of <cite data-doc="Md. Code" data-path="27">Article 27, Subtitle Health-Controlled Dangerous Substances of the Maryland Code</cite> relating to the manufacture, distribution, sale, possession, or administration of substances covered therein. A police officer shall first request a person suspected of loitering under this subtitle within a drug-free zone to leave the premises. Failure to obey the police officer shall subject the person to arrest. City Code, 1976/83, art. 19, §58C(b), (d) Ord. 89-375 Ord. 90-561A