It is against Florida criminal laws for an underage person (21) to sell, serve, possess or consume alcoholic beverages. Serving alcohol to a minor can be a felony: child abuse. If alcohol is present in the same space as a minor the law permits a presumption, albeit rebuttable, but a presumption nonetheless, which means an arrest and a trip to the courthouse. The proving of actual possession is the trick, but the trump is the arrest and the charge. A minor (under 21) can work in an establishment that serves alcohol, he/she can serve it, but cannot consume. If you are underage and in a car that is stopped you will be arrested. The arrest leads to a criminal charge, a South Florida criminal defense lawyer to defend you and an anxious South Florida jury to examine the evidence. All in all the best route is to say no when invited into a car or a party where underage people are holding, drinking, offering and or consuming alcohol. A criminal arrest can derail life plans, so wait until you are 21.