Because they spend such a lot of their time in courts !
Dominoes. Falling one at a time.
Time to get a new fence...
Normal day at the office, when one guy notices his coworker distraught. He goes over to his cubicle and sees him looking for something on the floor. They spend half an hour looking for it, when the guy starts picking his nose:
They spent the first nine months of their lives dodging hangers.
Witch 2: "I get a lot of hexercise."
Because they have a quidditch.
Court is adjourned
Because it was charged with battery.
Cat-burgers! (burglars)
Burglars don't knock !
They don't like getting close to the net!