Cal. Gov't Code § 70201

(a) The Judicial Council or registrar of voters shall certify the results of a vote to unify the municipal courts and the superior courts in a county.
(b) Unification of the municipal and superior courts in a county requires an affirmative vote of a majority of all superior court judges in the county eligible to vote and a majority of all municipal court judges in the county eligible to vote.
(c) On certification, a vote in favor of unification of the municipal and superior courts in a county is final and may not be rescinded or revoked by a subsequent vote.