I'll be the first to admit the legal drinking age in the U.S. is both arbitrary and silly. At 16 (in most states) you can operate a 4,000-pound vehicle capable of killing. At 18 you can serve in the military and be given access to a wide assortment of weapons. But drinking alcohol? That has to wait until the ripe old age of 21 (in most states) for some strange reason. I'd like to think there is science behind the choice of the number, but there isn't.
The age of 21 was selected because that was when English Common Law identified a person as an official adult — meaning they could vote and become a knight. Apparently drinking, voting and swordplay all fall into the same maturity category for lawmakers. If you look at maturity scientifically, the legal drinking age should be closer to 25. That is about when the frontal lobe — the part of the brain that lets you see the future consequences of your actions — is fully formed and connected to the rest of your brain. But we all know science and lawmakers rarely coexist, so 21 to drink it is.
Ridiculousness of the legal drinking age aside, Kennedy was dead wrong in her actions. At 50, her frontal lobe is fully formed and she was well aware of the consequences behind her actions. Part of being a grown-up — especially part of being a parent —is modeling good behavior for kids. Children learn what they see, and if you are teaching kids that laws are irrelevant you can't expect them to have the ability to discern which laws are circumventable. Especially teens, who tend to look for any excuse to bend the rules. I speak from experience. My mom used to provide alcohol to my friends and I when we were teens. Her rationale was we'd get it somewhere, so she'd rather we get booze in a safe way and drink at home. I understand her reasoning, but it isn't a choice I'd make for my kids. I know firsthand that seeing my mom's blatant disregard for the law encouraged me to make choices I may not have, had I been shown that rules were meant to be followed.
By buying the booze and hosting the party, Kennedy was effectively undermining the legal system as a whole, and if we lose our legal system you can guarantee the loss of civilized society won't be far behind. As citizens, we don't get to pick and choose which laws we will follow, it's an all-or-nothing package deal. Am I making a big deal out of a few kids drinking? Maybe. But it isn't really them I take issue with; they didn't know better. It's the grown adult who set the party up who is to blame. To paraphrase Maya Angelou: Kennedy knew better, she should have done better. Hopefully the legal punishment she receives encourages the kids she failed to do better than her.
More on teens and drinking
How to deal: Teenage drinking
Can teenage drinking lead to alcoholism?
Should parents allow teens to drink under adult supervision?