According to German law (Jugendschutzgesetz), §9:From here.
- Minors 14 years of age and older may drink undistilled alcoholic beverages, such as wine and beer, when accompanied by a Custodial Person,
- Minors 16 years of age and older may drink undistilled alcoholic beverages, such as wine and beer, without accompaniment, and
Note that the act of drinking itself is not illegal for a minor. It is only the offering or facilitating of alcohol that is illegal (and punishable).
- Adults (18 and older) may drink distilled spirits without restriction as well.
This law would make more sense than the current legal regime in the United States. Consumption of alcohol by a minor "regulatory" offense (it has no "victims") and is among the least serious in the U.S. (it doesn't even count against you in a law school admissions evaluation), but these offenses are probably the single biggest reason that people who would otherwise not have criminal records end up in the criminal justice system.
Eliminating a reason for law enforcement intervention reduces the risks of myriad very seriously bad things that can happen any time that they happen, so an opportunity to greatly reduce the number of law enforcement contacts and people with criminal records, by decriminalizing behavior that is legal in most of the world would be a positive development.