Held a red hot iron and walked three spaces. Then wounds were bandaged and left for three days If the wound was getting better after three days, you were innocent. If the wound was clearly not getting better you were guilty.
You were tied up and thrown into water. If you floated you were guilty.
Used by noblemen who had been accused of something. Fight in combat with their accuser. If you won you were right. If you lost you were most likely dead.
A gibbet was just outside of the town. Hung on gibbet and left to rot for a warning to other people. This did work for a short wile but the crime was overwhelming they couldn’t keep that many people on the gibbet at once.