Welsh law

Compurgation, also called trial by oath, wager of law, and oath-helping, was a defence used primarily in medieval law. A defendant could establish his innocence or nonliability by taking an oath and by getting a required number of persons, typically twelve, to swear they believed the defendant's oath. The wager of law was essentially a character reference, initially by kin and later by neighbours (from the same region as the defendant), often 11 or 12 men, and it was a way to give credibility to the oath of a defendant at a time when a person's oath had more credibility than a written record.

13th-century Welsh manuscript

boundary between England and Wales

Galanas in Welsh law was a payment made by a killer and his family to the family of his or her victim. It is similar to éraic in Ireland and the Anglo-Saxon weregild.