sentences:  That is, Missouri law prohibits minors from possessing or purchasing alcohol.Thus, when the National Minimum Drinking Age Act of 1984 came into effect on January 1, 1985, Missouri was in no danger of losing federal highway funds.A minor in possession (MIP) of alcohol or a business or person which furnishes alcohol to a minor is guilty of a misdemeanor, although for sellers there are numerous defenses and exceptions.