Exodus 18:24-26

24So Moses listened to his father-in-law and did everything that he had said.

25Moses chose able men from all Israel and made them heads over the people, leaders of thousands, of hundreds, of fifties and of tens [from the highest to the lowest judicial levels].

26And they judged the people at all times; they would bring the difficult cases to Moses, but every minor dispute they judged and decided themselves.