The California 170.6 challenge: one per side, no reasons, and a deadline that depends on the assignment

California gives every side one peremptory challenge to the judge. No reasons are required, none may be demanded, and the assignment is changed "without any further act or proof."

Because it is unreviewable and irreversible, the rules around it are all about timing and counting — when the motion must be made, and how many are left.

What it does

CCP 170.6(a)(1): a judge, court commissioner or referee of a superior court "shall not try a civil or criminal action or special proceeding of any kind or character nor hear any matter therein that involves a contested issue of law or fact when it is established as provided in this section that the judge or court commissioner is prejudiced against a party or attorney or the interest of a party or attorney."

How it is established — subdivision (a)(2): by "an oral or written motion without prior notice supported by affidavit or declaration under penalty of perjury, or an oral statement under oath," that the judge is prejudiced against a party or attorney "so that the party or attorney cannot, or believes that he or she cannot, have a fair and impartial trial or hearing."

Note the phrase "or believes that he or she cannot." The declaration asserts a belief. Nothing has to be proved, and nothing is investigated.

And it is automatic — subdivision (a)(4):

If the motion is duly presented, and the affidavit or declaration … is duly filed or an oral statement under oath is duly made, thereupon and without any further act or proof, the judge supervising the master calendar, if any, shall assign some other judge, court commissioner, or referee to try the cause or hear the matter.

Where there is no other judge available in that court, "the Chair of the Judicial Council shall assign some other judge … as promptly as possible."

The deadlines

This is where most 170.6 motions are won or lost. The section sets different clocks for different assignment patterns, all in subdivision (a)(2).

And an absolute outer limit, whatever the route:

• In no event shall a judge, court commissioner, or referee entertain the motion if it is made after the drawing of the name of the first juror, or if there is no jury, after the making of an opening statement by counsel for plaintiff, or if there is no opening statement, after swearing in the first witness or the giving of any evidence or after trial of the cause has otherwise commenced.

For cases the paragraph does not specifically cover, "the procedure specified herein shall be followed as nearly as possible."

Notice to everyone else — subdivision (a)(3): a party making the motion in a civil action "shall serve notice on all parties no later than five days after making the motion."

What does not spend the challenge

A useful provision, easy to miss:

The fact that a judge … has presided at, or acted in connection with, a pretrial conference or other hearing, proceeding, or motion prior to trial, and not involving a determination of contested fact issues relating to the merits, shall not preclude the later making of the motion.

So a judge who has heard a scheduling matter, or ruled on a motion that did not resolve contested facts going to the merits, can still be challenged at the proper time. What forecloses the motion is a determination of contested fact issues relating to the merits — not mere prior involvement.

After a reversal on appeal

The section carries a specific re-entry point:

A motion under this paragraph may be made following reversal on appeal of a trial court's decision, or following reversal on appeal of a trial court's final judgment, if the trial judge in the prior proceeding is assigned to conduct a new trial on the matter. Notwithstanding paragraph (4), the party who filed the appeal that resulted in the reversal of a final judgment … may make a motion under this section regardless of whether that party or side has previously done so. The motion shall be made within 60 days after the party or the party's attorney has been notified of the assignment.

That is the one place where a side gets a second challenge — the successful appellant, against the judge whose judgment was reversed, on a 60-day clock.

One per side

Subdivision (a)(4) again:

• Except as provided in this section, no party or attorney shall be permitted to make more than one such motion in any one action or special proceeding. In actions or special proceedings where there may be more than one plaintiff or similar party or more than one defendant or similar party appearing in the action or special proceeding, only one motion for each side may be made in any one action or special proceeding.

Per side, not per party. Ten co-defendants share a single challenge between them. That makes the decision to use it a matter to coordinate with co-parties before anyone files.

Continuances — subdivision (a)(5): "Unless required for the convenience of the court or unless good cause is shown, a continuance of the trial or hearing shall not be granted by reason of the making of a motion under this section."

Using the challenge is not, by itself, a way to move a trial date.

The other route: disqualification for cause

CCP 170.6 is a peremptory challenge. CCP 170.1 is the for-cause ground list, and it is long. A judge shall be disqualified where, among other things:

Personal knowledge — 170.1(a)(1): the judge has personal knowledge of disputed evidentiary facts. And the judge is deemed to have such knowledge if the judge, the judge's spouse, a person within the third degree of relationship to either, or that person's spouse "is to the judge's knowledge likely to be a material witness."

Prior role as a lawyer — (a)(2): the judge served as a lawyer in the proceeding, or advised a party on a matter involved in it. The judge is deemed to have done so if, within the past two years, a party or a party's officer, director or trustee "was a client of the judge when the judge was in the private practice of law or a client of a lawyer with whom the judge was associated," or a lawyer in the proceeding "was associated in the private practice of law with the judge."

Financial interest — (a)(3): a financial interest in the subject matter or in a party, including one held by a spouse or minor child living in the household, or held as a fiduciary. The judge "has a duty to make reasonable efforts to inform himself or herself" about those interests.

Relationships — (a)(4) and (a)(5): the judge, the judge's spouse, a person within the third degree of relationship to either, or that person's spouse is a party or an officer, director or trustee of a party; or a lawyer in the proceeding, or a lawyer's spouse, is the spouse, former spouse, child, sibling or parent of the judge or the judge's spouse, or is associated in private practice with a lawyer in the proceeding.

How a for-cause disqualification works

The judge acts first — CCP 170.3(a)(1): a judge who determines himself or herself disqualified "shall notify the presiding judge … of his or her recusal and shall not further participate," except as CCP 170.4 allows, unless the disqualification is waived.

Waiver — subdivision (b)(1): a judge who has disclosed the basis on the record "may ask the parties and their attorneys whether they wish to waive." A waiver "shall recite the basis for the disqualification, and is effective only when signed by all parties and their attorneys and filed in the record."

Two grounds can never be waived — subdivision (b)(2):

(A) The judge has a personal bias or prejudice concerning a party. (B) The judge served as an attorney in the matter in controversy, or the judge has been a material witness concerning that matter.

And the judge must not lobby — subdivision (b)(3): the judge "shall not seek to induce a waiver and shall avoid any effort to discover which lawyers or parties favored or opposed a waiver."

Rulings already made — subdivision (b)(4): where grounds are first learned of or arise after the judge has made rulings but before judicial action is complete, the judge shall disqualify — but "in the absence of good cause the rulings he or she has made up to that time shall not be set aside" by the replacement judge.

If the judge will not step down — subdivision (c)(1): any party may file with the clerk "a written verified statement objecting to the hearing or trial … and setting forth the facts constituting the grounds." It "shall be presented at the earliest practicable opportunity after discovery of the facts." Copies are served on each appearing party, and the statement is personally served on the judge alleged to be disqualified, or on that judge's clerk if the judge is present in the courthouse.

What a disqualified judge may still do

CCP 170.4(a): notwithstanding disqualification, the judge may:

• (1) take any action or issue any order necessary to maintain the jurisdiction of the court pending assignment of a judge who is not disqualified;
• (2) request any other judge agreed upon by the parties to sit in their place;
• (3) hear and determine purely default matters;
• (4) issue an order for possession prior to judgment in eminent domain proceedings;
• (5) set proceedings for trial or hearing;
• (6) conduct settlement conferences.

Otherwise nothing — subdivision (d): "Except as provided in this section, a disqualified judge shall have no power to act in any proceeding after his or her disqualification or after the filing of a statement of disqualification until the question … has been determined."

Striking a bad statement — subdivision (b): where a statement of disqualification "is untimely filed or if on its face it discloses no legal grounds for disqualification, the trial judge against whom it was filed may order it stricken."

Filed mid-trial — subdivision (c)(1): where the statement is filed after trial or hearing has commenced — by the start of voir dire, the swearing of the first witness, or the submission of a motion for decision — the judge "may order the trial or hearing to continue." The disqualification issue goes to another judge, and if disqualification is found, "all orders and rulings of the judge found to be disqualified made after the filing of the statement shall be vacated."

A deeming rule — subdivision (c)(2): in a single-judge court or an all-purpose assignment, where the matter "has been set for trial or hearing 30 or more days in advance before a judge whose name was known at the time," the trial or hearing "shall be deemed to have commenced 10 days prior to the date scheduled" as to any grounds known before that time.

That is a trap. On a case set well in advance, the practical deadline for a for-cause statement on known grounds is 10 days before the trial date, not the trial date itself.

One statement only — subdivision (c)(3): a party may file no more than one statement of disqualification against a judge "unless facts suggesting new grounds … are first learned of or arise after the first statement was filed." Repetitive statements "shall be stricken by the judge against whom they are filed."

Choosing between them

A short checklist

1. Identify the assignment type the day it happens. Fifteen days for an all-purpose civil assignment, five days before a known trial date, at assignment in a master calendar court.
2. Coordinate with co-parties. It is one motion per side, so the first to file spends it for everyone aligned with them.
3. Do not assume prior appearances have burned it. Only a determination of contested fact issues going to the merits forecloses the motion.
4. Serve notice on all parties within five days of making the motion.
5. Do not expect a continuance. CCP 170.6(a)(5) says the motion alone is not a reason for one.
6. If you won an appeal and drew the same judge for retrial, you get a fresh challenge — 60 days from notice of the assignment.
7. For cause, move at the earliest practicable opportunity — and on a case set 30 or more days out, treat the real deadline as 10 days before trial.
8. Verify the statement and serve the judge personally. CCP 170.3(c)(1) requires both.
9. File one statement. A second without genuinely new facts will be stricken by the judge it targets.

Where these sections live

• CCP 170.1 — Grounds for disqualification
• CCP 170.3 — Recusal, waiver, and the verified statement
• CCP 170.4 — What a disqualified judge may do
• CCP 170.6 — Peremptory challenge
• CCP 1005 — Notice periods for motions
• CCP 1008 — Reconsideration and renewal of motions
• CCP 396b — Motion to transfer for improper venue
• CCP 397 — Grounds for changing the place of trial

This page explains what the Code says. It isn't legal advice, and local rules on all-purpose assignments and master calendar practice vary by court.