A party making a peremptory challenge by motion or affidavit of prejudice regarding an assigned judge must submit it in writing to the assigned judge within 20 days after service of the order assigning the judge to the coordination proceeding. All plaintiffs or similar parties in the included or coordinated actions constitute a side and all defendants or similar parties in such actions constitute a side for purposes of applying Code of Civil Procedure section 170.6.
Rule 3.516.Motions under Code of Civil Procedure section 170.6
Division 4. Parties and Actions · Chapter 7. Coordination of Complex Actions · Article 2. Procedural Rules Applicable to All Complex Coordination Proceedings · Last amended 2007 · Last verified July 29, 2026
In one sentenceRule 3.516 requires a peremptory challenge to the assigned coordination judge to be submitted in writing within twenty days after service of the order assigning that judge, and treats all plaintiffs or similar parties as one side and all defendants or similar parties as the other side under Code of Civil Procedure section 170.6.
Full Text of Rule 3.516
Plain-English Summary
Code of Civil Procedure section 170.6 lets a party disqualify an assigned judge through a peremptory challenge, without having to show actual bias. Rule 3.516 adapts the timing of that right to the coordination setting: a party making such a challenge to an assigned judge must submit it in writing to that judge within twenty days after service of the order assigning the judge to the coordination proceeding.
The rule also solves a problem unique to coordination. Section 170.6 ordinarily limits each side of a case to one challenge, but a coordinated proceeding gathers plaintiffs and defendants from many separate original actions, which could otherwise multiply the number of available challenges well beyond what the statute contemplates for a single case. Rule 3.516 fixes that by defining every plaintiff or similar party across all the included or coordinated actions as one side, and every defendant or similar party as the other side, so the one-challenge-per-side structure of section 170.6 works the same way in a coordinated proceeding as it does in an ordinary single action.
Frequently Asked Questions
How long does a party have to challenge the assigned coordination judge under Code of Civil Procedure section 170.6?
Twenty days after service of the order assigning that judge to the coordination proceeding.
Must the challenge be submitted in writing?
Yes, in writing to the assigned judge.
How are the two sides defined for a peremptory challenge in a coordinated proceeding?
All plaintiffs or similar parties in the included or coordinated actions form one side, and all defendants or similar parties form the other side.
Why does rule 3.516 need its own rule for defining sides?
Because a coordination proceeding combines many separate actions, and without this rule, section 170.6's one-challenge-per-side structure could multiply well beyond what the statute contemplates for a single action.
Amendment History
Rule 3.516 renumbered effective January 1, 2007; adopted as rule 1515 effective January 1, 1974; previously amended effective June 19, 1982, and January 1, 2005.
Source & verification. Rule text is reproduced verbatim from
the Judicial Council of California. Adopted by the Judicial Council of California.
Last verified July 29, 2026.
· Official source
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