My dad suggested I take a few photos of the university. I had hesitated previously because parts of it are not the most beautiful. The top photo, for instance, is of the back of the School of Modern Greek. The bottom photo, however, is the front, which makes for a much nicer view.
Part (or all) of the problem stems from a strange Greek law which makes it illegal for police to step foot on university soil. This law was passed in reaction to a tragedy which occurred in the early 70s (I believe), in which student protesters were killed by riot police. It was meant to prevent this tragedy from reoccurring. What it means practically is that the university is an 'OPEN FOR BUSINESS' sign for every sort of criminal one can imagine.
Other students have reported seeing very open drug transactions going on outside their classroom windows. If you look a little too hard in the grass, you can find discarded syringes (yes, heroin is a problem here -- although generally, it seems to me that drugs are less of a problem here than in the US).
On top of all this, students decide every few months to protest something or other (just a couple months ago there were violent demonstrations in response to some of the soccer team's player trades), and they go ahead and burn a building. Just this past Friday they torched the post office located on campus.
In spite of all this, the campus actually feels surprisingly safe and calm, at least when I'm there during the day. I guess all the shenanigans happen at night after the students hit Thessaloniki's famous night scene.