Every government (or administration) has to decide between two goals that are fundamentally at odds.
They can either pass and enforce laws (rules) that follow the idealized morals of the society, or they can enforce sensibly. It's the choice between idealism and realism.
The administration of Carnegie Mellon is caught in this issue right now: do they do as they usually have and turn a blind eye to underage drinking, or do they enforce realistically, caring more about safety than catching minors consuming and frats providing?
College students will continue drinking underage, no matter what the school tries. By enforcing idealism, they're creating a more dangerous environment, with people drinking hard alcohol irresponsibly outside the confines of the amnesty policy, instead of drinking bad beer on campus within the school's safety net.
Tying in my earlier post, I believe that young, intelligent minds should be allowed to make their own moral decisions as long as they're safe. The amnesty policy increases safety on campus. Drinking a drink or two, even underage, is safe. Students are no longer free to try a drink or two, illegally, and make up their own minds and learn their own lessons.
Making alcohol taboo will only increase abuse.
To the administration of Carnegie Mellon: let us make mistakes. Let us learn our own lessons with alcohol in a safe environment, instead of making us experiment in a more dangerous one. Your idealism now will cause more problems later.
(This sounded a lot better in my head)