Tell your boss. Thats the most reasonable thing to do. First of all, your not the boss and you don't have the right to make those type of decisions, Second ,you don't want anything to happen to the customers and third ,you may get fire for not saying anything to the boss when knowing that person was drunk or sending that person home when your not the one who makes those decisions.
You And Another Employee Come To Work At The Same Time. You Notice The Other Employee Is Drunk. Which Would Be The Most Appropriate Action To Take?
What I would do is tell the person to go home and then tell the boss why I sent him/ her home not to get ne one in trouble but to make sure that he/she is safe n so as well as the costumers.