Some states have laws against riding a bicycle on a street or highway while under the influence of drugs or alcohol (cycling under the influence, or CUI). Other states apply traditional DUI/DWI laws to cycling while under the influence of drugs or alcohol. And some states don't have a specific CUI law, and don't apply traditional DUI/DWI laws to riding a non-motorized vehicle, such as a bicycle.
In Maryland, traditional DUI (driving under the influence) and DWI (driving while impaired) laws apply to motor vehicles and do not explicitly include bicycles. Maryland's Transportation Code § 21-902 does not categorize bicycles as motor vehicles. Therefore, cyclists are not subject to the same DUI or DWI laws as motor vehicle drivers. However, this does not mean that riding a bicycle under the influence of alcohol or drugs is without consequence. Local ordinances may address the issue, and cyclists can still be stopped by law enforcement and potentially face other charges or civil consequences if their behavior is deemed unsafe or they are a danger to themselves or others. It is always advisable to avoid cycling under the influence for safety reasons.