The first night of my last cruise while sitting on my balcony I saw and heard a drunk next door attempt to stand on a plastic table on his balcony so that he could urinate over the side of the ship. He was pulled away from disaster at a close to falling over the side of the ship moment by another of his drunk pals.
I know the cruise lines, do not remember which lines, has footage of one person going to the railing, disrobing, and jumping in off the top deck. I remember one husband jumping ship due to being fed up with being with his wife...or she with him. They saved him. Imagine the rest of that cruise.
I know it is easier to collect money from the cruise industry if you can prove they are responsible, but I think many times the passenger drank too much.