Legal Question in Criminal Law in Michigan

You don't tell us which law your 'research' uncovered that applies only to license holders and not employees, or even what state law you were charged under. MCL 436.1701(1) is a 60 day misdemeanor w/ a mandatory $1000 fine and community service that prohibits knowingly selling or furnishing alcohol to someone under 21, or if the person fails to make a diligent inquiry into whether the person is under 21. This would apply to you, based on what you have said. It is not limited to "licensees", "owners", etc. It's not limited to commercial transactions / sales. If you're at a tailgater this weekend and give someone a beer, or tell someone they can have beer from your keg or cooler and you know they are under 21 or you don't diligently try to find out if they are under 21, then you could be charged. Whether you're a store clerk or a tailgater, the easiest way to "make a diligent inquiry" is to look at the person's driver's license, state-issued ID card, etc. If the license/ID looks legitimate, then that may be your defense. If the license/ID looks bogus, then it may not be a defense. In most of these sting operations where charges are issued, the undercover person is less than 21, tries to buy beer/liquor, and the clerk doesn't even ask for ID; if ID is requested and the person presents a valid card showing they are under 21 and the sale still goes through, they'll be charged, too. The point of the operations is to make sure liquor license operations and their employees check ID, don't sell to minors, show through their routine operations that training and procedure follow the law.