You can report the illegal drinking of alcohol. Underage drinking outside and drinking in unlicensed establishments are considered emergency situations. When they are not handling emergency situations, officers from your local police precinct will respond to complaints about underage drinking in bars or clubs or anyone drinking alcohol outdoors.
Call 911 to report:
Underage drinking of alcohol outside or in a parked vehicle
Drinking of alcohol in an unlicensed establishment, social club, or bodega