Kings can excommunicate their citizens and jail them, but they can not take them out of jail. Once in jail, they are no longer a citizen of a land. There will be people assigned that will be able to unban jailed players, but it will be a personal ability and not responsable authority. That means whoever will have the ability to unban, might chose not to use their ability to do so. This works similar to the jail rules. You get in for a defined time (usualy) but after that time you won't get out automated, it only means you could get out if you ask it. In prison you are kind of deprived of your rights, but once you are out, previous crimes should not put a stain upon your character.