The California Apartment Association is asking a state appeals court to strike down San Francisco’s so-called “Empty Homes Tax,” arguing that the measure violates property owners’ constitutional rights.

In a friend-of-the-court filing prepared by the Pacific Legal Foundation on CAA’s behalf, the association supports the San Francisco Apartment Association’s challenge to the law.

Background on the vacancy tax

San Francisco voters approved the “Empty Homes Tax” (Proposition M) in 2022, which sought to penalize owners of residential properties left vacant for more than 182 days per year. The City claimed the measure would encourage owners to rent vacant units and thus ease the housing shortage.

In October 2024, the San Francisco Superior Court sided with the SFAA and other plaintiffs, finding the tax unconstitutional on multiple grounds. The court held that the measure violated the Takings Clause, Substantive Due Process, and Equal Protection provisions of the Constitution, and conflicted with the state’s Ellis Act, which protects property owners’ right to exit the rental business. San Francisco appealed that decision.

CAA’s position: the vacancy tax is an unconstitutional taking

CAA’s amicus brief, filed Oct. 17, 2025, argues that San Francisco’s vacancy tax unlawfully strips property owners of their fundamental right to exclude others from their property—a cornerstone of property ownership protected by the Fifth Amendment.

“The purpose of the Empty Homes Tax is to compel the occupancy of residential units against the property owner’s will,” the brief states. “It is now the City that controls the right to exclude.”

The brief emphasizes that the measure’s true intent is not to raise revenue, but to force owners to rent their private properties to third parties, effectively converting private housing into a public resource without compensation. CAA and PLF argue that this constitutes a categorical physical taking, as defined by the U.S. Supreme Court in cases such as Cedar Point Nursery v. Hassid.

Moreover, the brief contends that even if the measure is not deemed a per se taking, it still violates the “unconstitutional conditions” doctrine, which bars governments from coercing citizens into giving up constitutional rights in exchange for avoiding penalties. In this case, property owners are faced with an unlawful choice: either rent out their property against their will or pay an escalating tax penalty of up to $20,000 per year.

CAA joined this case because the issues extend well beyond San Francisco. Similar vacancy tax proposals have surfaced in other California cities, raising serious constitutional and policy concerns about government overreach into private housing decisions.

Next steps

The appeal is now fully briefed and awaits the scheduling of oral argument before the California Court of Appeal.