California's No-Horizontal-Stare-Decisis Rule: How an Accident Became Law

California is the largest common-law jurisdiction where appellate courts don't follow each other—and it happened by accident. In Part 1 of this two-part episode, Michael Shipley explains how Bernard Witkin’s treatise reflections on case dicta became binding law, why the federal circuit model works differently, and what the rule costs practitioners and trial judges every day.

Key points:

• The Witkin origin story: No California Supreme Court decision actually establishes the no-horizontal-stare-decisis rule. It developed through dicta, then appeared in Witkin's first edition—which courts then cited as authority.
• The federal contrast matters for forum strategy: In the Ninth Circuit, Miller v. Gammy binds all panels within the circuit to follow the first published decision on an issue. California trial courts, by contrast, face conflicting appellate authority and must guess which rule the Supreme Court would adopt under Auto Equity—a burden one trial judge called being "appointed to the Supreme Court for temporary purposes."
• Stare decisis isn't jurisdictional (probably).
• Unpublished opinions create tension.
• The pros: California's rule allows multiple perspectives on emerging issues and prevents the first Court of Appeal decision from locking in statewide law before the Supreme Court weighs in.
• The cons: The rule creates uncertainty, burdens trial courts, and leads to inadvertent inconsistencies on procedural issues too minor for Supreme Court attention—splits that can persist for years or even decades. (In anti-SLAPP law, it took 13 years before Baral v. Schnitt decided how to handle mixed causes of action.)
• Publication practices hide the problem: Many conflicts never surface because courts strategically leave decisions unpublished, masking the frequency of divergent reasoning and making the appellate landscape harder to navigate.

Listen to Part 1 now for the full discussion on how California got here and what it costs practitioners—then tune in to Part 2, where Shipley covers forum shopping, the anti-SLAPP mixed-causes-of-action case study, and his proposed reform: precedential transfer.