I should start with a description of the library: my city's main branch has 4 floors. One wall is composed almost entirely of windows with a type of design similar to scaffolding that extends outwards on the inside of the building over the reading terrace. Similar to this:
One day last year I came to work and shortly after the entire building was being evacuated. I looked up and there was a young man STANDING ON THE SCAFFOLDING on the fourth floor. Hence why we had to evacuate; one misstep and he could have fallen four floors down as around the reading terrace it is an open design. Shortly after the building was emptied the police and emergency services showed up and had to climb up and rescue the guy.
Apparently he and his girlfriend had gotten into an argument in the library earlier that day and she had broken up with him and told him "he should kill himself". So he climbed the scaffolding intending to jump off. But of course once he got up there, he decided that he wanted to live, but couldn't figure out how to climb back down!
Crazy library patrons: at least climb the OUTSIDE of the building. Or even better: avoid having your crazy break up arguments inside the library altogether.