In Shear Development Co., LLC v. California Coastal Commission (April 23, 2026, S284378) __ Cal. __, the Supreme Court clarified the standard of review applicable to Local Coastal Plan (LCP) interpretation and narrowed the circumstances under which the California Coastal Commission (Commission) may exercise appellate jurisdiction over local coastal development permits. The Court reversed the Second District Court of Appeal, holding that the Commission lacked appellate jurisdiction over San Luis Obispo County’s approval of a single-family residential development in Los Osos.

Key Takeaways

• LCP interpretation is a legal question. Courts apply independent judgment —not substantial evidence review—when determining whether the Commission properly exercised appellate jurisdiction based on the interpretation of an LCP.
• Deference is not automatic when agencies disagree. Where the Commission and a local government offer competing interpretations of an LCP, courts evaluate each under the Yamaha framework. When neither interpretation is more persuasive, no deference is owed to either.

Background

Shear Development Co. (Shear) acquired eight residential lots in Los Osos in early 2000s and obtained County approval of a coastal development permit (CDP) to construct single-family homes in two phases. The CDP authorized construction of four homes in the first phase and conditioned construction of the remaining homes on the future completion of the community wastewater system. The Commission appealed the County’s approval to exercise its appellate jurisdiction and, on de novo review, approved the first phase but denied the second phase due to uncertainty regarding the timing and availability of the community wastewater system. Shear constructed the four approved residences.

The Los Osos Wastewater Project was completed in 2016. Shear then applied for a CDP in 2017 to build the remaining homes. The County ultimately approved construction on three of the four remaining lots—with one lot excluded due to concerns about a then-endangered species—finding that wastewater capacity was adequate.

The Commission again appealed the County’s determination and denied the permit. The Commission asserted appellate jurisdiction on two grounds: (1) that the project site was located within a Sensitive Coastal Resource Area (SCRA); and (2) that the development was not “the” principal permitted use because zoning allowed multiple principal uses.

Shear filed a petition for writ of administrative mandate challenging the Commission’s decision on the grounds that it lacked appellate jurisdiction and abused its discretion in denying the CDP. The trial court concluded that the Commission had appellate jurisdiction based on the project’s location in an SCRA but rejected the Commission’s alternative argument that jurisdiction existed because the development was not the sole principal permitted use. On the merits, the trial court upheld the Commission’s denial of the permit, concluding that substantial evidence supported the Commission’s finding that the lots lacked sufficient access to wastewater disposal.

Shear appealed. The County, as amicus curiae, argued that the Commission lacked appellate jurisdiction because, under the County’s interpretation of its LCP, the project site was not located within an SCRA. The Second District affirmed the trial court, concluding the Commission properly exercised appellate jurisdiction based on the project’s location in the SCRA. The appellate court, however, declined to determine whether the Commission had jurisdiction on the principal permitted-use issue.

Supreme Court Decision

The Supreme Court reversed the appellate court.

Independent Judgment Applies to LCP Interpretation

The Court held that the question of whether the Commission properly exercised appellate jurisdiction based on an LCP is a question of law. Because LCPs are enacted law, courts must independently interpret them rather than defer to agency determinations.

No Deference to Either Agency

The Court next addressed whether deference was owed to the Commission’s or the County’s interpretation of the LCP. Applying the Yamaha framework, it concluded that neither agency was entitled to deference because neither had demonstrated a comparative interpretive advantage or a more persuasive showing that its interpretation was correct. Accordingly, the Court applied de novo review to the legal questions without deferring to either party.

The Project Was Not Located in an SCRA

In assessing appellate jurisdiction, the Court found the LCP ambiguous regarding the geographic scope of the SCRA designation and, considering the LCP’s text and extrinsic evidence, concluded it was not intended to include urban areas. Because the project was in an urban area, it was not within an SCRA, and the Commission therefore lacked jurisdiction on that ground.

No Jurisdiction Based on Principal Permitted Use

The Court also rejected the Commission’s alternative basis for jurisdiction—that the project was not “the” principal permitted use. Because the proposed development was one of several principal permitted uses for the site, the Court held that this did not trigger appellate jurisdiction. Instead, it observed that because the development was one of several principal permitted uses, the statute did not confer appellate jurisdiction, which applies only where a project is not among any of the principal permitted uses.

Sara Helms & Nina Berglund