I'm over 21. What happens if I'm caught buying alcohol for my underage friends?

If you are 21 years or older and you purchase or provide alcohol to anyone under 21, you can be charged with Unlawful Transactions with Minors, which is a misdemeanor punishable by up to a $1,000 fine and 6 months in jail.  Even worse, if anything bad happens as a result of that transaction, you could be held liable.

What are the consequences for a DUI in Montana?

If a police officer asks me to take a breath test do I have to do so?