For a long time at Rice University they, in not so certain terms, allowed underage students to drink in private parties on campus. While going there many of us thought this helped prevent drunk driving. Hearing about friends getting DWIs was very unusual, and generally limited to off campus students trying to drive themselves home when they shouldn't.
More recently, they've started to crack down on underage drinking, and now the police blotter fills a column in the campus newspaper with a series of "Driver arrested on suspicion of DWI." Hopefully this is a result of them cracking down on drinking and driving too, but I fear that to some extent it's because they are forcing the parties off campus.