California's high court just changed how attorneys remove a judge.
For nearly 50 years, a peremptory challenge under Code of Civil Procedure section 170.6 could not be questioned, no matter how it was used. In May 2026, the California Supreme Court changed that for the first time since 1977. Three consequences for anyone who files, or defends against, one.
What section 170.6 has always allowed
California Code of Civil Procedure section 170.6 lets a party or attorney disqualify a judge without proving actual bias. File the motion within the statutory deadline, state a belief that the judge is prejudiced, and disqualification follows automatically. No hearing, no inquiry into whether the belief is genuine. It has functioned, since 1957, as one of the few truly automatic procedural tools in California litigation.
The pattern that forced the question
The case that reached the Supreme Court, J.O. v. Superior Court of San Joaquin County, grew out of a conservatorship proceeding. After friction between a judge and an attorney from the San Joaquin County Counsel's office in an earlier case, that office filed more than 300 section 170.6 motions against the same judge over less than four months, eventually forcing the judge's reassignment away from an entire category of specialized proceedings.
That pattern is exactly what the Court's 1977 decision in Solberg v. Superior Court had said courts could never examine. Solberg held that even systematic, coordinated use of section 170.6 did not violate separation-of-powers principles, and that courts could not look behind a disqualification motion to ask why it was filed.
What the Court held
On May 28, 2026, in a unanimous opinion, the California Supreme Court partially overruled Solberg. Section 170.6 remains constitutional on its face. But the Court held that blanket abuse can, in certain circumstances, materially impair the judiciary's core function of administering justice, and announced a new framework, modeled loosely on the burden-shifting structure of Batson v. Kentucky.
An opposing party who timely objects and makes a prima facie showing that a section 170.6 motion reflects a bad-faith blanket policy, rather than a genuine belief in bias, can trigger judicial review. That review happens at a hearing before a different judge, where the burden shifts to whoever filed the motion to articulate a good-faith, case-specific basis for believing the challenged judge is prejudiced.
The hearing judge then decides whether the pattern reflects a legitimate exercise of the statute or an improper blanket policy, and grants or denies the challenge accordingly.
Three consequences for practicing attorneys
What changes, in practice, for anyone who files a section 170.6 motion, or opposes one:
A blanket pattern is no longer automatically shielded
A single section 170.6 filing is still presumptively valid on its face, but a party or office that files them against the same judge repeatedly now has real exposure if an opponent can show a pattern.
A challenge can now trigger its own hearing
Opposing counsel who suspects a blanket policy can force a hearing before a different judge, adding a real procedural step, and a real delay, to what was previously an automatic, unreviewable filing.
Repeat filers now have a reason to document their reasoning
Public defenders, county counsel offices, and high-volume litigation groups that use section 170.6 routinely now have practical reason to keep a case-specific record of why each challenge was filed, since that record may need to be produced later.
The decision does not touch the ordinary, single-case use of section 170.6, which remains exactly as automatic as it was the day before the ruling. What changed is the ceiling: a tool built for individual cases can no longer be deployed as a standing policy against one judge without the possibility of being questioned.
For litigators who rely on section 170.6 as a routine part of practice, that is a meaningfully different tool than the one they had in April.
Archivar
The Archivar Editorial Desk
Researched and fact-checked against multiple independent sources. General information for attorneys, not legal advice.
Sources: J.O. v. Superior Court of San Joaquin County, 19 Cal.5th 753 (2026), California Supreme Court, decided May 28, 2026; WilmerHale, client alert (June 3, 2026); GMSR Appellate Lawyers, case summary; Mondaq, legal analysis (July 30, 2026).
