Does Pullman Abstention Apply To Federal Takings Claims Post-Knick?

According to the U.S. Court of Appeals for the Ninth Circuit, the answer is a definitive yes.

Generally speaking, Pullman abstention permits a federal court to stay a federal claim to allow a state court to resolve a state issue that could either eliminate or narrow the scope of the federal claim. In order to invoke Pullman abstention, the federal claim must also touch on a sensitive area of social policy and involve an undecided question of state law.

In Gearing v. City of Half Moon Bay, the Gearings asserted that under California's Housing Crisis Act and California legislation passed in 2019 (Senate Bill 330), they were permitted as a matter of right to build housing on their properties. The City of Half Moon Bay asserted that the City's Land Use Plan severely restricted housing developments in the area where the properties were located, and that under the Land Use Plan the Gearings first needed to submit and the City needed to approve a master plan for the