The Urim and the Thumim

Saul is put in the awkward position of having to execute the guy responsible for winning the battle. The people basically protect Jonathan and protest that the whole thing was a dumb thing to say. But while Saul is trying to figure out what's going on here, who's the guilty party? Because he hears about this. They bring out the Urim and the Thumim and it's actually said that they are cast. And so the speculation is that well, maybe they were flat on one side and so they would land either one side or the other.