Central 46 (中央四十六, Chūō Shijūroku): The Central 46 serve the Shinigami royalty (the ruling class of all Soul Society). They are made up of 40 wise men and 6 judges, selected from all of Soul Society. They are sealed into an enclave in Seireitei called Seijōtōkyorin (清浄塔居林) which no one else may enter, regardless of their military or civilian status. They act as a supreme judiciary organization whose authority puts it in direct control of the legal system. They handle all rulings on Shinigami and souls who have violated prohibitions. Their orders are absolute and no decision has been known to be overturned.
Laws
1. It is against the law for a Shinigami to give their spiritual power to Humans.
2. It is against the law for a Shinigami to use forbidden Kidō.
3. It is against the law for any citizen of Soul Society to create weapons of a dangerous nature not sanctioned by the feudal government. To do so is treason.
4. It is against the law to attack a captain. To do so is treason.
5. It is against the law to commit terrorist action(s) or attempt overthrow of the balance of Soul Society. To do so is treason.
6. It is against the law to commit murder.
7. It is against the law to kill a Human that a Shinigami has not been ordered to kill.
8. It is forbidden for a Shinigami to acquire or attempt to gain Hollow-like powers.
9. It is against the law for the Gotei 13 to meddle in the affairs of the noble families unless the family in question breaks one of the laws of Soul Society beyond a shadow of a doubt.
10. It is a crime for a Shinigami to remain in the Human World longer than a certain time limit.
11. All visits to the human world must be authorized.
Punishment
Exile: Certain crimes allows for the punishment of exile, commonly stripping a Shinigami of their powers and banishing them to the real world.
Detention: A punishment not well known among the citizens of Soul Society is the detention of high-level Shinigami. It is commonly reserved for those who have either broken the law, quit the Gotei 13 or those who just seem dangerous and mentally unstable (as per the government's interpretation). This is carried out by the Onmitsukidō.
Imprisonment: The Central 46 can sentence a Shinigami to be held in an underground prison for a set amount of time. The prison has eight levels, which prisoners are confined in based on the severity of their crimes.