California Code, Penal Code - PEN § 1462.25

(a) A defendant formally charged with a violation of Vehicle Code Section 14601 in one court (“the first court”), against whom a formal charge of a violation of Vehicle Code Section 14601 is pending in one or more other courts, may state in writing his or her agreement to plead guilty or nolo contendere to some or all of the charges pending in the other courts, to waive trial or hearing in the other courts, and to consent to disposition of the case in the first court. The defendant's agreement is ineffective unless the district attorney for the other county approves in writing. Upon receipt of the defendant's agreement and the district attorney's approval, the clerk of court in the other court shall transfer the pending matter to the first court, and transmit the papers or certified copies. The prosecution of each transferred matter shall proceed in the first court as part of the case pending against the defendant there, but shall be limited to proceedings upon the defendant's plea of guilty or nolo contendere, and sentencing or probation. If the defendant pleads not guilty, the clerk shall retransfer the transferred case to the court of origin, and the prosecution shall be resumed in that court. The defendant's statement that the defendant agreed to plead guilty or nolo contendere shall not be used against the defendant.

(b) The procedure specified in subdivision (a) may be used only if the defendant is represented by counsel in the other courts, or the defendant has expressly waived his or her right to counsel in the other courts.

(c) A defendant may request appointment of counsel in the other courts by a written request. Upon receiving the defendant's written request, the other court shall appoint counsel to represent the defendant if he or she otherwise qualifies for appointed counsel.

(d) The appearance of the defendant in proceedings transferred pursuant to subdivision (a) shall not commence the running of time limits under Section 859b, 860, 861, or 1382.