At least yours did it on the toilet seats.

About ten years ago, I got called into a meeting by building management with my office manager. Someone in my company was regularly pooping in one of the bathroom stalls and using their poop to paint on the walls. Using absence records compared against data watch swipes compared against the dates of the events, the office manager and I were able to determine who it was. Could never prove it for 100%, not enough that my boss was comfortable enough for me to confront her, but I have no doubt: it was our receptionist, a young woman in her early 20s. Office Manager and I took to referring to the culprit as the "poop-tiste." We had to laugh, otherwise I know I would have cried.

I lived about a mile from my office. From that point on, I'd literally drive home anytime I needed to use the bathroom during the day.