Correct me if I’m wrong, but wouldn’t it matter what state you crossed over in. For example, in Minnesota, we allow people to tend bar at age 18, but not to drink until 21. So, if there were an MIP law on the books, I would think this wouldn’t be possible. Bascially what I would do is put the 12 packs in the trunk or in a cooler or what not, don’t try to hide them because that would indicate intent to smuggle. Essentially, I believe no more than 1 in 20 are questioned more intensively then just a couple questions through the window. If the border patrol DOES single you out and tries to be an asshole about it, remember you haven’t crossed into the US until they let you through. If it’s legal for you to drink and possess alcohol in Canada, if they say you can’t legally possess liquor in the US, simply say that you were unaware…your friends with whom you’re staying in the US asked you if you could bring them some Canadian beer and you didn’t think anything of it. Worst case is they hold you up for a few hours and then confiscate the beer, but it’s unlikely…I don’t really think you can be hit for a crime, because unless you try to do something stupid like hide bottles in your socks, what are you really doing illegal if you never actually cross the border with beer in your possession…all you’ve done is possess beer in a country where it’s legal for you to do so. Most border agents try to intimidate you but that’s how they can tell if you’re telling the truth. Just don’t lie. Having said that, I’m not a lawyer, it wouldn’t hurt to try to get an official answer from the powers that be because what I’m saying seems “logical” to me, but the law isn’t always logical.