Can I have the police apprehend these people?

Long story short: I told my roommate that his female friend could sleep in my room while she was visiting. Two nights ago she left a condom on my dresser. Last night some male friends of his came over (these people have been giving me mean looks and showing aggressive body language for months because I broke up with their friend more than a year ago and he transferred colleges as a result). I had been studying for a midterm out at the kitchen table, but when these mean people came over, I left. They drew a in my notebook. I am completely upset that they could possibly be allowed to come into my apartment and vandalize my things in a ual way and not be punished. I am now spending valuable time trying to figure a way for them to get justice - my midterm is tomorrow. I don't want to have to worry about them, I want to study in peace.