SB 9, SB 10, and the Contest Over Who Gets to Say Yes

The Duplex That Broke the Truce

In September 2021, Gavin Newsom signed two bills that did something California zoning law had not done in the better part of a century: they told a single-family homeowner that the city could no longer stop them from adding a second unit, or a third, or a fourth, to their own lot — regardless of what the local council thought about it. SB 9 let almost any parcel zoned for one house become two, and let that same parcel be split in half so each new lot could hold two more. SB 10 let cities opt in to zoning up to ten units near transit or in “urbanized” areas without the years-long environmental review that had killed a thousand smaller projects before they broke ground.

Five years on, SB 9 and SB 10 look less like a single reform than the opening shot in a war that is still escalating — one that has since pulled in a lawsuit against Huntington Beach, a “builder’s remedy” that punishes cities for stalling, a closed loophole for charter cities, a transit bill that succeeded where SB 10 quietly failed, and, as of this July, the Newsom administration suing five cities directly. It is also one of the few live political fights in this state where “liberty” is not a rhetorical prop for one side — it is the argument being had by both.

Two Freedoms, One Empty Lot

Isaiah Berlin’s distinction between negative and positive liberty — freedom from interference versus freedom to achieve — is usually invoked to explain arguments about welfare states and markets. Housing turns out to be a near-perfect test case, because SB 9 forces the two concepts to collide inside a single vacant backyard.

The negative-liberty case for SB 9 is the classic property-rights argument, and it is a strong one: the person who owns the lot should be free to build on it, subject to the same safety and structural codes as anyone else, without a planning commission’s veto. A zoning ordinance that lets a neighbor block a duplex three doors down is, on this account, just interference by another name — coercion exercised through a permit desk instead of a badge. That a majority of a city council voted for the restriction doesn’t make it less coercive to the owner who wanted to build.

The positive-liberty case is different and arguably more central to why the bill exists at all: a renter priced out of the city where their job is has, in Berlin’s sense, been rendered unfree to pursue the life they could otherwise have — not by a person standing in their way, but by decades of zoning that made new housing next to impossible to build. On this account, the state stepping in isn’t an assault on liberty; it’s a correction of an artificial scarcity that was itself imposed by government, one that happens to have been the single biggest predictor of who could afford to live in coastal California and who couldn’t.

Both readings are honest. What makes SB 9 uncomfortable for anyone with a tidy ideology is that it is a state mandate overriding local government in order to expand what an individual property owner may do — central authority deployed, deliberately, to shrink local authority and enlarge private discretion. A conventional libertarian playbook has “smaller government” and “local control” pointing the same direction. SB 9 is the case where they don’t.

Whose Local Is It, Anyway

The counter-argument city councils actually made wasn’t really about liberty at all — it was about democracy. Zoning law in California is, formally, an exercise of the police power delegated to municipalities; a council that reflects its residents’ preferences, the argument goes, has as much claim to legitimacy as Sacramento does, and arguably a tighter feedback loop with the people it governs. When the Legislature overrides that with a statewide mandate, it isn’t liberating anyone from coercion — it’s just relocating the coercion from a body voters can unseat at the next city election to one three hundred miles away.

That argument found its sharpest test in Los Angeles, a charter city, whose city attorney argued (and a Superior Court judge initially agreed, in 2023) that SB 9 couldn’t reach it at all — charter cities have a state constitutional grant of authority over “municipal affairs” that ordinary state statutes can’t simply preempt. For a moment, the loophole threatened to swallow the law in every big city with a charter. The Legislature closed it in 2024 with SB 450, which folded charter cities in explicitly, imposed a hard 60-day approval clock, and — tellingly — barred cities from inventing extra design standards to slow-walk applications the letter of the law couldn’t stop. Each round of this fight follows the same shape: a city finds a technical gap, the state closes it, and the next bill is a little more prescriptive than the last.

The Escalation SB 9 and SB 10 Set Off

SB 10 itself mostly fizzled — it was opt-in, and almost no city opted in, which is its own quiet lesson about how much can be accomplished by permitting liberty versus mandating it. But its premise — upzoning near transit without CEQA review — didn’t die with it. SB 79 (2025) revived the idea as a statewide mandate rather than a menu option, forcing transit-adjacent upzoning cities can’t decline. In between, the Legislature built out an entire enforcement architecture that didn’t exist in 2021:

• SB 35 / SB 423 — ministerial, no-discretion approval for multifamily projects in cities that miss their state-mandated housing targets, effectively suspending local review as a penalty.
• The builder’s remedy — if a city’s housing element isn’t certified by the state, developers can propose projects that ignore the local zoning code almost entirely. Huntington Beach tested this by refusing to comply and got sued by the Attorney General for its trouble; five more cities were sued directly by the Newsom administration in July 2026.
• AB 2011 and SB 684 — converted underused commercial corridors and small residential lots into by-right housing sites, extending the “your city doesn’t get to say no” principle past single-family zones into strip malls and infill parcels.
• AB 130 — shrank the acreage threshold for CEQA-exempt builder’s-remedy projects from five acres to four, tightening the noose further on cities still slow-walking approvals.

Each of these is SB 9’s logic — override local discretion to expand what an owner or developer may build — applied to a new category of land or a new category of city resistance. What began as a carve-out for duplexes has become the default assumption that local land-use control is a privilege the state extends conditionally, not a right cities hold outright.

Mitigated Negative Declaration vs. the Full EIR

The CEQA carve-outs mentioned above aren’t a single lever — they work by taking different rungs off a ladder of review that, until this decade, gave a city three ways to say a project needed more scrutiny before it would approve one. A Negative Declaration says a project’s initial study found no evidence of significant environmental harm; a Mitigated Negative Declaration (MND) says the harm is real but reducible to “less than significant” by conditions attached before approval; a full Environmental Impact Report (EIR) is required whenever neither is true. The standard that pushes a project up to a full EIR is deliberately stacked against the agency: under the “fair argument” rule from No Oil, Inc. v. City of Los Angeles (1974) and Friends of “B” Street v. City of Hayward (1980), if there is substantial evidence that a project might have a significant effect, an EIR is required — even if the city has just as much evidence on the other side. It is a low bar, built to favor more review, not less.

The housing-streamlining bills didn’t lower that bar. They took the ladder away entirely for qualifying projects, because CEQA in California only ever attaches to discretionary government action — a decision where the city could still say no on the merits. SB 35 and SB 423 make approval ministerial for qualifying projects, which places them outside CEQA’s reach altogether under Public Resources Code §21080(b)(1); AB 2011 and SB 684 do the same for commercial-corridor and small-lot infill housing respectively. Berkeley found out how absolute that is in 2021, when it tried to block a 260-unit SB 35 project at 1900 Fourth Street partly over the site’s significance to Ohlone descendants as a shellmound — there was no MND to contest and no fair-argument threshold to clear, because there was no discretionary decision left for the city to make. The Court of Appeal ordered the city to approve the project anyway in Ruegg & Ellsworth v. City of Berkeley, and Berkeley ultimately paid roughly $4 million in damages and fees for the delay.

AB 130, passed as a budget trailer bill in mid-2025, went further still: rather than exempting specific project types, it wrote a straight statutory CEQA exemption for qualifying infill housing up to 20 acres, with a narrower cap — tightened from five acres to four by SB 158 that October — carved out for builder’s-remedy projects specifically. A city that can’t get its housing element certified no longer just loses its zoning veto; for anything under that acreage cap, it loses CEQA review as a bargaining chip too. That is the mechanism behind what critics of the builder’s remedy actually mean by “unacceptable plans”: not that the projects are illegal, but that a city with real, unresolved concerns about a project’s site, traffic, or environmental footprint has no procedural path left to force a harder look at it before approval is compelled.

The Bigger Number Behind the Bills

Zoning fights read like a legal dispute, but the pressure that has forced Sacramento’s hand five years running is closer to a solvency crisis. California’s median home price hit $854,000 in March 2026 — roughly double the national figure — and the state has bled net domestic population for 25 straight years, over 200,000 residents a year in most of them. Nearly half of Californians rent, and as Christopher Calton put it recently in Law & Liberty, “as rising rents or life changes compel them to look for housing elsewhere, fewer people are willing to replace them.” Calton frames the state’s choice as “build or bye,” comparing Houston — the only major U.S. city with no comprehensive zoning code — against Detroit, whose population fell from 1.85 million in 1950 to around 600,000 by 2000. Houston keeps regulatory compliance costs near 7 percent of a home’s price against roughly 40 percent nationally, issues permits by-right in about ten days, and posts a median home price under half of California’s; Detroit’s homes are cheaper still, but for the reason nobody wants — nobody’s bidding for them.

SB 9 and its successors are, in that light, California trying to buy its way back toward the Houston side of that ledger without giving up the thing Houston never had to begin with: comprehensive local zoning discretion. Every bill in the escalation — the builder’s remedy, SB 423’s ministerial approvals, the CEQA carve-outs — is a workaround for not being willing to just abolish zoning outright, the way Houston effectively has. Calton, citing economists Chang-Tai Hsieh and Enrico Moretti, puts real numbers on the stakes: fixing the regulatory bottleneck in a handful of the country’s most productive-but-restricted metros, San Francisco and San Jose among them, could add on the order of a third to national GDP growth — the “spatial misallocation of labor” case for treating this as more than a local zoning squabble.

What This Actually Tests

The honest version of the “social liberty” question here isn’t “is SB 9 libertarian.” It’s that liberty, applied to land, was never going to resolve into one answer, because land is the resource where one person’s freedom to build is inseparable from another person’s freedom to be governed by people they elected — and both of those are real liberties, not decoys for the other side’s actual interest.

Calton’s own fix is Houston’s: abolish zoning outright and let the market clear on price. The Georgist fix is different but rhymes with it — instead of the state relitigating, parcel by parcel and bill by bill, exactly which local restrictions survive and which get preempted, tax the land itself according to its unimproved value, and let owners keep the full value of whatever they choose to build on it. That reframes the fight entirely — a duplex isn’t something a neighbor’s veto or a state override decides; it’s what an owner does once holding vacant, underbuilt land next to a rail stop stops being free. Nobody has to win the argument about whether Sacramento or the city council is the more legitimate authority, because the incentive does the work zoning fights over SB 9 have been trying, badly, to do by statute since 2021.

Until that argument gets a real hearing, expect the current pattern to continue: a city finds a new way to say no, the Legislature finds a new way to make no cost something, and each cycle narrows, just a little more, how much of a “local affair” land use actually is anywhere in California.