The NFL offseason is always an eventful time for NFL stars even though they are nowhere near a football field in most cases for months at a time. It's during these times of the year when most players go on long vacations or do things like host 'Jeopardy!
Other guys chose to spend at least some of their time at clubs and parties. When you mix massive human beings who are used to beating people up on a daily basis like Aaron Donald with some booze things can get out of hand. That's exactly what happened in this case.