Not too much in Torah, I believe: I think the beginning of the court system can be traced to Ex. chap. 18 where Jethro, Moses's father-in-law, urged Moses to delegate dispute resolution duties. I think for composition of the Sanhedrin, one would probably have to go to the Talmud.
The righteous hold the very fabric of the universe together, and when a group of righteous, talented souls like this "Magnificent 71" are assembled, great things are triggered and unfold in the divine realm.