Motion to Disqualify a Judge in California: Grounds, Filing, and Timing

To file a motion to disqualify a judge in California, you have two tools: a peremptory challenge under Code of Civil Procedure section 170.6, which requires no reason but must be filed within tight deadlines, and a for-cause challenge under section 170.1, which requires a written verified statement laying out specific facts showing bias or a conflict. The peremptory route is nearly automatic when timely. The for-cause route is harder, slower, and risky if your facts are thin.

Start With the Peremptory Challenge if You Can

Before drafting anything longer, check whether CCP 170.6 is still open to you. Under that statute, you file a sworn statement that you believe the assigned judge is prejudiced against your side, and the court must grant it. You do not have to explain, prove, or even genuinely hold the belief in any provable sense. It just has to be timely.¹

Timing is the whole game. If the assigned judge is known at least 10 days before the trial or hearing, you must file at least 5 days before that date. In a criminal case assigned to one judge for all purposes, you have 10 days after notice of assignment. In a civil all-purpose assignment, you have 15 days. Once trial begins, meaning jury selection starts, the first witness is sworn, or opening statements begin, the option is gone. You also cannot use a peremptory challenge at settlement conferences or case management conferences.¹

Each side gets one peremptory per case. Co-plaintiffs share one; co-defendants share one. If your co-defendant already used it, the peremptory door is closed and you have to go the for-cause route.

Grounds for a For-Cause Challenge

CCP 170.1 requires a judge to step aside whenever a reasonable person aware of the facts would doubt the judge’s impartiality. That is the broadest ground. The statute also lists specific situations that require disqualification on their own:²

The judge, a spouse, or a close relative has personal knowledge of disputed facts, or is likely to be a witness.
The judge previously represented or advised a party, or handled the same legal issues in private practice. This also applies if a party was a client of the judge, or of a lawyer the judge practiced with, within the past two years.
The judge, a spouse, or a minor child in the household has a financial interest in the outcome, including stock in a company involved in the litigation or a fiduciary connection to the case.
A close relative of the judge or the judge’s spouse is a party, an officer or director of a party, or a lawyer in the proceeding.
Any other relationship or circumstance that would lead a reasonable person to question the judge’s impartiality, including personal friendships or past disputes with a party or attorney.

Under this statutory standard, the appearance of bias is enough. You do not have to prove the judge is actually biased, only that a reasonable observer would reasonably doubt their impartiality.³

How to File the Verified Statement

The filing itself is governed by CCP 170.3(c). The statute calls it a “written verified statement,” meaning you sign it under penalty of perjury. People often call it a motion, but the verification is what makes it work.⁴

The statement has to lay out concrete facts that fit one of the grounds in CCP 170.1. Saying the judge “seems unfair” or “has ruled against me” does not survive. You need specifics: financial disclosure records showing stock ownership, documentation of a prior attorney-client relationship, a described personal connection to a witness. If you are relying on the general appearance-of-bias ground, describe the conduct or circumstances that would cause a reasonable observer to doubt impartiality.

You file with the court clerk and serve copies on every party or attorney who has appeared in the case. The judge must be personally served, either directly or through their clerk while the judge is present at the courthouse or in chambers. Those service requirements come from the statute itself.⁴

A challenged judge normally cannot rule on their own disqualification. But CCP 170.4(b) lets the judge strike the statement without sending it to another judge if it is untimely or fails to state any legal ground on its face. That is where most weak filings die. A statement that recites conclusions without supporting facts gives the very judge you are trying to remove the authority to throw it out.⁵

You get one statement per judge, unless genuinely new facts emerge after the first one. Repeat filings that recycle the same grounds get stricken.⁵

When You Have to File

CCP 170.3 requires filing “at the earliest practicable opportunity” after you learn the facts supporting disqualification. That phrase sounds flexible but courts read it strictly, in days and weeks rather than months. In Tri Counties Bank v. Superior Court (2008) 167 Cal.App.4th 1332, a party who waited more than seven months after learning of the grounds had the statement struck as untimely.⁶

If the conflict existed before assignment, file before the judge takes substantive action on your case. If it surfaces mid-case, file as soon as you know. Courts are especially skeptical when a party loses a ruling and only then discovers a concern about the judge’s impartiality. That pattern reads as judge-shopping.

What the Judge Does Next

Once you file a proper statement, the challenged judge has 10 days from filing or service, whichever is later, to either consent to disqualification or file a written verified answer contesting your allegations.⁴ If the judge consents, the presiding judge assigns a replacement.

If the judge contests it, another judge decides the question. The parties have five days to agree on who that judge should be. If they cannot agree, the chairperson of the Judicial Council picks one. Neither side can file a peremptory challenge against the judge chosen to decide the disqualification.⁴

The reviewing judge usually decides on the papers: your verified statement, the challenged judge’s answer, and any written arguments. A live-testimony hearing is possible if disputed facts require it, but most decisions happen on paper. You carry the burden. While the review is pending, the challenged judge generally cannot act on the case.⁵

What Happens to the Judge’s Earlier Rulings

A successful disqualification does not automatically erase what came before. Under CCP 170.3(b)(4), rulings made before the grounds for disqualification arose or were discovered stay in effect unless the replacement judge finds good cause to set them aside. Rulings that were decided on the merits and rest on sound reasoning are likely to survive.⁴

Orders issued after you file the statement are treated differently. When trial has already begun, the challenged judge may keep the proceeding moving while the disqualification is reviewed. If the judge is then disqualified, everything ordered after the filing date is vacated.⁵ Filing sooner means fewer post-filing rulings to fight about later.

If the Disqualification Is Denied

You cannot appeal a denial in the ordinary sense. CCP 170.3(d) says the determination is not an appealable order. Your only route is a petition for writ of mandate in the Court of Appeal, filed within 10 days after service of the order. If notice was served by mail, standard mail-service extensions under CCP 1013 apply.⁴

Writ petitions are discretionary. The appellate court is not required to take the case, and you need to show the lower ruling was clearly wrong on the facts or the law. The filing fee is $775, with no fee in criminal or juvenile matters, and fee waivers are available for litigants who cannot afford court costs.⁷

Think Twice Before Filing a Weak One

A meritless statement gets stricken under CCP 170.4(b), and now the judge you accused of bias knows you could not back it up. That is not a position that helps you. Repeat filings against the same judge without new facts can be treated as bad-faith tactics, and courts have inherent authority to impose sanctions for abuse of process. Disagreeing with rulings, even strongly, is not the same as bias. Before you file, ask honestly whether your facts would persuade a neutral observer that the judge’s impartiality is reasonably in doubt. If the answer is no, the filing will hurt more than it helps.⁵

1
California Legislative Information. California Code of Civil Procedure 170.6
2
California Legislative Information. California Code of Civil Procedure CCP 170.1 – Disqualifications of Judges
3
Supreme Court of California. People v Freeman
4
California Legislative Information. California Code of Civil Procedure 170.3
5
California Legislative Information. California Code of Civil Procedure 170.4
6
Justia Law. Tri Counties Bank v Super Ct
7
Second Appellate District – California Courts of Appeal. Fees