This is how tithings used to work. Ten men would be grouped into a tithing, and if any of those men were suspected of a crime, then the rest of the group either

This is how tithings used to work. Ten men would be grouped into a tithing, and if any of those men were suspected of a crime, then the rest of the group either had to prove their innocence or had to condemn the guilty party. If they did neither, all were equally punished for the crime. In principal, it strikes me as a good idea - it promotes collective good behaviour, and responsibility for ones peers.