Campus policies are generally enforced, especially in the dorms, but most punishments are not severe. For example, noise violations won’t get you in much trouble, and even after a couple warnings, the worst that might happen is you may have to write an essay on the importance of respecting your neighbors’ right to peace and quiet. However, drug use or possession will get you kicked out of the dorm immediately—and they check often. Alcohol is taken less seriously, but you will get a citation if you have it in the traditional dorms—two of these will land you in housing court, which could result in probation, and three will get you kicked out of school. However, other than in the dorms, campus isn’t terribly strict. The University police officers are there to keep students safe more than to keep them in line—they have enough work trying to keep down crime, so they tolerate parties as long as they don’t get too out of hand. The strongest punishment you'll see from a University police officer is probably a parking ticket.
In general, most of the rule-breaking on campus involves minor violations, so the punishments handed down aren't that severe. Of course, if you do something really out of hand, you can expect some pretty harsh consequences. For example, after the Virginia Tech shooting in 2007, a U of L student called in a hoax bomb threat and was arrested by the FBI. He was immediately expelled from the University and sentenced to six months of home incarceration and 160 hours of community service. However, that’s an extreme case, and most students on campus will never even have to speak with a University police officer, unless they just want to be friendly and say hi.