Oakland had a problem. Predatory lenders were aggressively targeting its residents, extracting exorbitant interest fees and imposing surprise balloon payments.1 Throughout the city, home values cratered and poverty levels climbed.2 Families faced foreclosure, leaving once-vibrant neighborhoods blighted and abandoned.3
Versions of this foreclosure crisis were unfolding across the nation, but city leaders knew that Oakland’s residents — largely low income and nonwhite4 — were particularly susceptible.5 So they took decisive action. In 2001, Oakland’s city government passed a promising ordinance that strictly regulated lending practices and the secondary mortgage market.6 Eight days later, the California state legislature passed its own mortgage regulations, but they lacked the ambition of the Oakland ordinance.7 Yes, the state package regulated subprime mortgages, but to a lesser degree than Oakland’s ordinance.8 The state law also overlooked the secondary market entirely.9 And it had an additional purpose: while Oakland’s ordinance aimed to curb bad practices, California’s law also tried to preserve the mortgage market’s efficiency.10
In 2005, a consumer-credit trade association sued to invalidate Oakland’s ordinance, arguing that the state law preempted it.11 The state legislature had not intended to override the local regulation; indeed, it had considered and rejected an express preemption provision.12 But no matter. In a 4–3 decision, the California Supreme Court held that “the Legislature ha[d] impliedly fully occupied the field of regulation of predatory practices in home mortgage lending.”13 There was no space for the city.14 Oakland’s prescient ordinance — enacted seven years before the Great Recession — was invalidated.
For cities, this is nothing new. State courts are quick to find local policies impliedly preempted by state statutes. This pattern merits reconsideration. At their best, municipal governments epitomize democratic values, promoting civic participation, policy experimentation, and community diversity. To realize these virtues, city halls need a doctrinal path to shore up their authority.
This Note looks to pave one, offering cities a new argument for their litigation arsenal. It proposes a substantive canon of construction — imperium urbis15 — for state courts faced with questions of implied preemption. When a court evaluates a local ordinance and a potentially preemptive state statute, the canon would tilt the scale in favor of local control. Preemption would be found only if the state statute expressly required it or if compliance with both would be impossible. Like many other substantive canons, a localist canon would ground itself in the promotion of a constitutional value: here, popular sovereignty as embodied in state constitutions’ local-government provisions.
This Note proceeds in three Parts. Part I briefly surveys the arguments for municipal power. Part II offers a primer on local-government law and discusses the threat of implied preemption. Part III introduces the canon by describing its mechanics, outlining its doctrinal foundation, and demonstrating its potential for application.
I. Cities as Centers of Democracy
Cities play a vital role in our democratic system. They have been described as the “perfect exercise of self-government,”16 a place to inculcate citizens “with civic spirit, a taste for public affairs, and political skills.”17 With increasing frequency, local governments are at the center of a global economy, tasked with an array of vexing policy challenges — COVID-19, policing, affordable housing, and climate change, to name a few.18 Cities need policymaking discretion to respond to these pressing questions. This Note takes as its starting point that local governments are a necessary component of our democratic system and that protecting local power is a normative good. This Part overviews some of cities’ most extolled virtues and acknowledges their chief critiques.
Cities are “critical sites for democratic participation and local political engagement.”19 As Alexis de Tocqueville put it: “Town-meetings are to liberty what primary schools are to science; they bring it within the people’s reach, they teach men how to use and how to enjoy it.”20 At the local level, “[d]emocratic participation is more possible.”21 Public officials are more accessible and outreach is less costly.22 An individual can play a far larger role in governance at the local level than at the state or federal level — a relatively smaller populace means a relatively larger voice.
Cities are also hotbeds of policy experimentation. Justice Brandeis famously defended federalism on the grounds that a state could be a “laboratory,” trying “novel social and economic experiments without risk to the rest of the country.”23 “If fifty states allow policy innovation and evaluation, then so much the better to empower ninety thousand local governments . . . .”24 Evaluating the success of their initiatives — be it living wages, sanctuary laws, tobacco restrictions, or environmental protections — can provide guidance on disputed policy questions.25 Successful policies can radiate out to other cities and up to other levels of government.
Furthermore, cities embody diversity. Cities’ proximity to their residents lets them tailor policies to local variation and adapt to changing exigencies.26 At the local level, racial and political minorities have a forum for expressing preferences that might be outvoted on the state or national stage.27 Thus, a state with strong city governments allows diverse polities to implement diverse policies. Citizens can “vote with their feet” and move to cities that best reflect their preferences.28 The result: a deep network of rich cities, with residents united by a common vision of what their community can be.
But for all its virtues, local power can be manipulated for pernicious ends.29 Cities have often been the handmaidens of inequality: adopting regressive land-use policies,30 barring protections for min-ority communities,31 and impeding progress during the Civil Rights movement.32 Chronically poor turnout in local elections can lead to governing bodies selected by whiter, wealthier constituents,33 and local policies can have deleterious effects that spill beyond a city’s borders.34 The question, then, is how to reinforce local autonomy to realize its benefits while avoiding the worst impulses of parochialism. Several scholars have outlined arguments to steer cities towards more normatively desirable ends.35 By assuming that cities can resist their most base urges, this Note instead explores how cities can withstand legal challenges to their authority.
II. The Implied Preemption Threat
Despite the merits of municipal governance, cities struggle to fully assert their policymaking authority. The disputes often play out through express and implied preemption. With the former, state legislatures explicitly preempt city ordinances in specified policy areas.36
The latter, while less discussed by scholars, is equally pernicious. A state legislature may pass a law that touches on the same area as a city ordinance. Even if the legislature has not signaled its intention to preempt a local ordinance, state courts may nevertheless read pre-emption implicitly into the statute, invalidating the local policy. The consequence is a hamstringing of cities’ crucial policymaking authority. This Part explores this threat. Section II.A begins with a background on the evolution of local authority and home rule, and section II.B elaborates on the perils of implied preemption.
A. A Primer on Local Power
For the United States’s first hundred years, local governments had no inherent lawmaking authority. State legislatures alone could create cities, grant them authority, change their boundaries, and abolish them altogether.37 In most states, cities could exercise only those powers expressly granted by the state and those that directly followed by implication.38 When construing these powers, courts resolved “[a]ny fair, reasonable doubt concerning the existence of power . . . against the [city].”39 Moreover, the Supreme Court declined to find protection for local governments in the Constitution,40 infamously calling cities “creatures of the State.”41 With overbearing states and unprotective courts, cities lacked the autonomy and flexibility to respond dynamically to urban problems.
Cities and their advocates fought back. In the post–Civil War period, reformists introduced new constraints on states’ powers over local governments.42 A flurry of constitutional amendments followed, many of which prohibited “special act” legislation that targeted specific cities.43 Rather than directly expand city autonomy, these reforms constrained state power.
As the Reconstruction Era progressed, rapid urbanization and population growth sparked a movement to strengthen local authority, and “home rule” was born.44 First passed in 1875 in Missouri, home rule amendments to state constitutions let residents draft, adopt, and amend their own city charters.45 So formed, home rule cities could exercise power over “local” or municipal affairs, so long as they did not conflict with state law.46 In addition to this “initiative” power, home rule offered cities an area of independent policymaking discretion — a realm in which states had little-to-no override authority.47 Most commonly, this so-called “immunity” power extended to areas of purely local concern, like matters of government structure and personnel. This model rolled outwards from Missouri, and by 1912, twelve states had enacted home rule amendments.48
Courts, however, struggled to draw a line between local and statewide affairs,49 and they inconsistently honored cities’ newfound immunity power.50 To solve these issues, a second wave of home rule reforms emerged in 1953.51 It granted local governments police powers, subject only to state-imposed restrictions.52 By removing the local-statewide distinction, this model sought to reduce courts’ roles in delineating the bounds of local power.53 In response to this proposal, nearly every state amended its existing local-government constitutional provisions or adopted new constitutions.54 Today, most states have enacted some variation of home rule amendments.55
B. The Threat of Implied Preemption
Despite their promise, home rule amendments have fallen short of securing a robust form of municipal authority. When litigants sue to invalidate local ordinances on the grounds of implied preemption, state courts must interpret the language of constitutions’ local-government provisions and, consequently, the extent of cities’ authority.56 Frequently, courts reach outcomes that restrict local power.57
Local-government scholars have long commented on state courts’ anti-city disposition58 — a disposition that looms ominously in implied preemption cases. In these cases, judges wade through ambiguity; they face a local ordinance and a state law that regulate the same subject, yet they lack clear guidance from the state legislature as to how to proceed. Judges must look to state constitutions for direction, but neither of the two home rule models is a paradigm of clarity. Judges thus have a great deal of discretion, a troubling state of affairs when “[r]easonable doubt concerning the existence of power is resolved by the courts against the municipality.”59
Strong state constitutional protections do not immunize cities from implied preemption challenges. California’s constitution, for example, vests cities with wide latitude.60 Cities can enact “all ordinances and regulations in respect to municipal affairs”61 that are “not in conflict with general laws.”62 The basis of many legal disagreements lies in this last phrase: “[N]ot in conflict with general laws.”63 To determine whether a local ordinance impermissibly conflicts with state general laws, courts look first to the law’s text. If there is no express pre-emption, courts assess the totality of the regulatory scheme, looking for “indicia of intent” that the legislature wanted to “fully occupy” an area.64 The analysis involves judicial discretion, leaving the fate of local ordinances in the hands of state judges, who are elevated by and arguably beholden to state party machinery.65 As Oakland experienced with its predatory-lending ordinance, judges often resolve ambiguity against cities, even when strong constitutional language might counsel otherwise.
The consequences reach beyond individual cases. In every challenge to a local ordinance, courts interpret the language of constitutions’ local-government provisions, defining the contours of local power through an ad hoc process.66 A decision against a city does not just invalidate an ordinance — it signals that the city has less power than it had thought, closing off a potential avenue for future policies. Inconsistent preemption analyses also create “a confusion that invites preemption challenges.”67 Businesses commonly bring suit, looking to invalidate local ordinances that would impose on them new burdens, be it through a higher minimum wage, a smoking ban, or a plastic bag prohibition.68 The mere threat of legal challenges has a chilling effect on local officials, dampening their willingness to develop forward-looking policies.69 For these reasons, scholars have described implied preemption as a “problematic shadow” over cities,70 one that imposes “severe constraints on local policy innovation.”71
While harmful, the ambiguity inherent in implied preemption cases presents an opportunity for cities to advance new legal arguments. Over time, favorable decisions would expand and buttress local authority. This Note now turns to that task.
III. Launching a Canon
A new substantive canon for state courts — imperium urbis — offers a possible solution. This Part introduces the canon. Section III.A outlines the canon’s mechanics, section III.B describes its doctrinal foundation, and section III.C sketches a possible application.
The imperium urbis canon is straightforward in its operation. A state court presented with a local ordinance and a potentially conflicting state statute would presumptively uphold the former. The state law would override only if there was an explicit preemption statement or if compliance with both laws would be impossible. The canon would effectively permit only express or impossibility preemption.72 Because it operates like a clear statement rule, imperium urbis would require state legislatures to expend political capital before expressly preempting cities.
Imperium urbis resembles the federal presumption against pre-emption, which disfavors federal preemption of state laws.73 Similar to how the federal presumption justifies itself by reference to federalism,74 imperium urbis grounds itself in the value of popular sovereignty.75 It would, however, be even stronger. While the federal presumption does not preclude a court from finding field and conflict preemption, imperium urbis would foreclose both.76
At the state level, imperium urbis is not functionally new. In 2020, the National League of Cities proposed a suite of model constitutional provisions designed to modernize state-local relations.77 Recognizing the threat of preemption challenges, its proposal included an amendment that would prohibit implied preemption.78 While functionally similar, the National League of Cities’s proposal requires a constitutional amendment; imperium urbis relies on existing constitutional values. Although more enduring, a constitutional amendment would require a significant and coordinated campaign, offering no immediate relief. In the meantime, advocates can turn to imperium urbis.
A few states already have something akin to this canon.79 Some state constitutions demand a “liberal construction” of local power to provide for “maximum local self-government.”80 This constitutional mandate has heft. The New Mexico Supreme Court has observed that its home rule amendment, which has a liberal-construction clause, “was clearly intended to devolve onto home rule municipalities remarkably broad powers” and “the utmost ability to take policymaking initiative.”81 Relying on a similar rationale, the Supreme Court of Illinois has stated that a state statute “must contain an express statement” to preempt a local ordinance.82 And relatedly, Alaska’s courts have disavowed field preemption.83 Although these constitutional protections often lead to more pro-city outcomes,84 cities remain vulnerable to implied preemption challenges.85 For these cities, imperium urbis would not be a standalone canon. Its arguments would instead be deployed to demand a more faithful application of these liberal-construction mandates.
Other scholars have advocated for state-specific canons rooted in their respective constitutional texts. For example, Professor Roderick Hills, Jr., has argued for New York courts to adopt an anti-preemption canon, basing his argument in the state constitution’s liberal-construction provision.86 Although New York’s constitutional language resembles that of Illinois,87 courts in New York have not adopted the same express-only approach.88 An anti-preemption canon, Hills writes, would “preserv[e] the structural value of home rule.”89
Imperium urbis is motivated by a similar desire to fortify home rule and local control, but it has a different justification. As discussed below, imperium urbis relies on the value of popular sovereignty, not the value of home rule itself. It is justified not by what the local-government provisions say but by the very fact of their existence. Accordingly, the strength of imperium urbis does not depend solely on constitutional text. Cities, regardless of whether they benefit from liberal-construction language, can invoke the logic of imperium urbis.
B. A Doctrinal Foundation
Substantive canons are “policy-based principles and presumptions that derive from the Constitution, common law practices, or normative concerns related to particular subject areas.”90 Although their applications differ — for example, the rule of lenity applies to ambiguous criminal statutes, the avoidance canon to cases implicating serious constitutional problems — their operation is similar: they put a thumb on the scale toward a particular outcome.91 A canon’s presumption is usually overcome only by clear statutory language.92 This section develops a framework for justifying substantive canons and then demonstrates how this framework supports the creation of imperium urbis.
Despite the ubiquity of substantive canons in Supreme Court cases,93 the Court has never clearly outlined what constitutes a substantive canon. Commentators even disagree on whether a Court pronouncement is a sufficient or even necessary condition for an interpretive rule to reach canon status.94 The debate is contentious, the answer unsettled.95
While there are several ways in which the Court justifies its canons,96 the promotion of a constitutional value is the most common.97 The Court frequently deploys a canon to protect a constitutional value when it lacks a hard-line rule to do so. As examples, the rule of lenity protects the constitutional norm of due process, and the federalism canons protect state sovereignty and the vertical distribution of powers.98
Considering these canons and others, then-Professor Amy Coney Barrett identified two prerequisites for a substantive canon: it “must be connected to a reasonably specific constitutional value” and “must actually promote the value it purports to protect.”99 Other scholars have similarly concluded that, where the Supreme Court “fail[s] to enforce a provision of the Constitution to its full conceptual boundaries,”100 substantive canons are a “backdoor mechanism” to enforce constitutional norms.101 Although these norms are unenforceable as strict limits on congressional power, strong substantive canons force Congress to consider constitutional values through the political process.102
Jurists of different judicial philosophies accept this constitutional-value approach. A committed textualist, Justice Barrett has doubted both the existence of some underlying constitutional norms and the connection between some norms and their implementing canons.103 Yet she still accepts canons that actually promote a valid underlying norm.104 Professors William Baude and Stephen Sachs’s originalist interpretive framework, while unsupportive of some canons,105 would likely still permit canons rooted in constitutional values.106 Finally, a purposivist judge could reason that a canon protecting an under-enforced constitutional norm effectuates the Constitution’s purpose.
At its core, imperium urbis is a pattern of argument that gives rise to a canon-like thumb on the scale. If enough courts adopt it, imperium urbis might be recognized as a canon.107 But so long as courts accept the logic of imperium urbis, whether they formally call it a “canon” is beside the point; cities’ ordinances will survive legal challenges with greater frequency.108
The constitutional value that underpins imperium urbis is popular sovereignty. It is a value that lies deep in America’s philosophical roots109 and that grounded the Founders’ understanding of legitimate government.110 The Supreme Court has recognized that “while sovereign powers are delegated to the agencies of government, sovereignty itself remains with the people.”111 From popular sovereignty flows a corollary principle: citizens have a right to alter or abolish their governments.112 The Tenth Amendment — with its reservation of power “to the States respectively, or to the people”113 — provides direct textual support for popular sovereignty as a federal constitutional principle.114
Popular sovereignty does not end with the Federal Constitution; the powers of states flow directly from their residents.115 Every state constitution but one116 has an explicit textual commitment to popular sovereignty — some version of “all political power is vested in and derived from the people,” government “originates with the people,” or state power comes from “the consent of the governed.”117 These provisions refer to both the original right of people to create their governments118 and their continuing right to change them.119 Because they retain the right to alter their state governments, citizens delegate to the states only part of their sovereignty — they never lose it entirely.120
Home rule cities embody popular sovereignty in two ways. First, the passage of local-government amendments is an opportunity for citizens to reshape the powers and structures of their government.121 When citizens add these provisions to their state constitutions, they are imposing new limits on state power122 and vesting new rights in themselves.123 Accordingly, a state must overcome new procedural hurdles before disrupting the boundaries, operations, or existence of a city; for example, a state might be prohibited from passing special legislation or be barred from chartering new cities.124 And as these amendments curtail state powers, they return power to citizens — the power to draft a city charter, vote on it, and incorporate a city. These provisions are thus a reallocation of sovereignty from the state back to the people.
Second, the process of chartering a city also exemplifies popular sovereignty. When residents follow the procedures of a home rule amendment to ratify a new charter and form a city government, they are relocating power from the state capitol to their city hall. In effect, it is a reclamation of the power to create and to govern cities. Importantly, the specifics of and eligibility for the chartering process vary from state to state, and not every city that can adopt a charter has done so.125 But when they do, cities demonstrate that they are not creatures of the state — they are creatures of the people.
So conceptualized, home rule amendments are reclamations of sovereign power by the citizenry, a striking instantiation of popular sovereignty. To respect this exercise of the people’s sovereignty, state courts should be reluctant to permit legislatures to trample on cities’ policymaking discretion. Imperium urbis encourages such restraint. Litigants could wield this argument, urging courts to apply a stringent pre-emption standard to promote the constitutional norm of popular sovereignty. Over time, a pattern of reasoning would emerge, eventually gaining recognition as a formal canon.
The logic of imperium urbis buttresses other arguments for city power. Because it grounds itself in the value of popular sovereignty, the canon does not rely on the specific text of any one local-government provision. Other localist arguments do, like Hills’s anti-preemption canon, which is based on a liberal-construction mandate.126 Rather than compete, these arguments reinforce one another. The stronger the buy-in to popular sovereignty as a constitutional value, the more likely it is that a court will generously construe a liberal-construction provision. And the stronger the liberal-construction mandate, the more likely a court will find popular sovereignty manifested in it. City litigants should filter these different arguments through their own constitutions — looking at the language of popular-sovereignty amendments, the strength of cities’ regulatory power, and the dictates of liberal-construction provisions — to craft compelling defenses of their authority.
Further, imperium urbis is not an argument that there is some unwritten constitutional right to local government. Others have eloquently argued for the existence of such a right, claiming that the Constitution presupposed the existence of local governments as necessary political vehicles127 and that individuals thus have an implied right to form cities.128 A few scholars have connected this inherent right of local self-government with popular sovereignty.129 While intriguing, this argument has never succeeded in court.130 For it to now gain traction would require a court to recognize a right that somehow always existed but has never been identified.131 By contrast, imperium urbis does not require the recognition of a preexisting right. Rather, it argues that the operative moment is the passage of local-government amendments. It is that act — the act of reallocating sovereignty from the state to the local level — that exemplifies popular sovereignty.
Notably, this reading of home rule amendments does not let cities escape all oversight. At the federal level, the Supreme Court develops its strongest canons where Congress has its broadest authority; when a strict limitation on Congress’s power would be inappropriate, a canon forces Congress to consider certain constitutional values.132 This reasoning applies well to city-state relations. State constitutions vest their legislatures with the authority to preempt local ordinances.133 This power has merit: states can serve as a check on harmful or discriminatory local policies, and statewide coordination is sometimes more effective than an assortment of local efforts.134 Rather than displace this authority, imperium urbis would require preemption to be explicit and intentional, forcing state officials to consider that city governments are exercises of popular sovereignty.
With this theory in place, consider an example.
Texas is an ideal state for imperium urbis. Its hostile state government135 has targeted liberal cities with express preemption,136 making it even more important for cities to avoid implied preemption to assert the bounds of their policymaking discretion. Fortunately, Texas has the tools for a successful imperium urbis argument: a strong commitment to popular sovereignty and a rich history of home rule. Illustratively, this section looks to a 2018 implied-preemption case, recounting its anti-city opinion and describing how the city could have advanced an imperium urbis argument.
By way of background, Texas courts proclaim a pro-city posture, insisting that the state legislature can only “preempt a subject matter normally within a home-rule city’s broad powers” with “unmistakable clarity.”137 The courts, however, take an inconsistent approach to “unmistakable clarity,” sometimes finding against the city even though the statutory text is loaded with ambiguity.
For example, Austin in 2018 passed an ordinance mandating that employers provide an hour of paid sick leave for every thirty hours worked.138 Several Texas business associations initiated a challenge.139 Among other things, the plaintiffs argued that the Texas Minimum Wage Act preempted the local ordinance.140 A Texas court of appeals agreed.141
In doing so, the court noted that the Act expressly barred Austin from imposing a higher minimum wage on private employers.142 To determine whether Austin’s paid-sick-leave ordinance fell within the Act’s scope, the court considered the meaning of the word “wage.”143 The Act itself gave no definition, so the court adopted a dictionary’s and held that paid sick leave fell within its ambit: because an employer would have to pay an employee who uses sick leave for hours that the employee did not work, the employee’s hourly pay would effectively be increased.144
In briefing, Austin parried this argument. If paid sick leave was considered wages, an employee’s minimum wage would include the value of their sick leave benefits.145 Thus, an employer that provided paid sick-leave could pay an hourly rate less than Texas’s minimum wage and still satisfy the statutory requirement.146 Given this absurdity, Austin asserted that the Act simply did not contemplate paid sick leave.147 The court left this argument unaddressed.
Admittedly, the court’s reasoning is plausible. But so is Austin’s. Troublingly, the court navigated this interpretive ambiguity by finding against the city, ignoring the requirement that a state law preempt a local ordinance only if it does so with “unmistakable clarity.” Imperium urbis could have encouraged the court to adhere to the unmistakable-clarity standard, potentially leading it to a different result.
Such an argument would begin with the Texas Constitution. It provides a rousing recognition of popular sovereignty: “[A]ll political power is inherent in the people, and all free governments are founded on their authority, and instituted for their benefit.”148 The people of Texas “have at all times the inalienable right to alter, reform or abolish their government.”149 As a state court put it, “true sovereignty lies in the people of Texas, not the government they created.”150
Applying a popular-sovereignty patina, consider the history of Texas’s Home Rule Amendment. The Constitution of 1876 — which remains in effect today151 — originally vested full control over cities in the state legislature. Cities of fewer than ten thousand residents were subject to generally applicable laws, and larger cities were subject to special legislation.152 When Texas had just a few large cities, the legislature had the bandwidth to pass special legislation for each of them.153 But as the number of large cities grew, requests from local governments swamped the legislature; by 1911, over twenty-five percent of the state’s legislation related to municipal affairs.154 City residents were eager for more control, and the legislature was willing to cede it.155
Pursuant to Texas’s constitutional amendment process, the state legislature sent a Home Rule Amendment to voters.156 In an exercise of their inherent sovereignty, the people of Texas approved the amendment in 1912.157 The Amendment provides that cities of more than five thousand may, by a majority vote, adopt a charter.158 Once adopted, a city can exercise any power granted to it by its charter, so long as it is not inconsistent with the state’s laws and constitution.159 A contemporaneously adopted provision stripped the state of its power to charter cities and regulate their internal structures.160 Anxious for autonomy, twenty-four cities drafted charters before the amendments took effect.161
Today, citizens continue to exercise their sovereign right to charter a city. During a 2013 campaign to ratify a city charter and become a home rule city, Sunnyvale, Texas, recognized that it was then subject to the “general laws of the State.”162 Home rule offered the alluring alternative of “self-governance in its ultimate form,” guided by a charter “based on community norms, values and priorities.”163 In a home rule city, Sunnyvale residents could “define for themselves how they want to be governed.”164 The citizens of Sunnyvale ultimately voted to adopt a charter and create a home rule city — a reclamation of government power and an exercise of popular sovereignty.165
The contours of a Texas imperium urbis argument are now sketched. In sum: Article I of the Texas Constitution enshrines the value of popular sovereignty, recognizing the right of Texans to create and shape their government as they see fit.166 With the passage of the Home Rule Amendment, Texans exercised their sovereignty by reorganizing their government, shifting power from the state to the local level. And every time Texans vote to charter a city, they reclaim and localize political power — itself an act of popular sovereignty.167
The City of Austin could have followed this roadmap in its paid-sick-leave litigation. It could have urged the court to apply a more robust “unmistakable clarity” test — Texas’s version of imperium urbis — to vindicate the value of popular sovereignty as embodied in local governments. In turn, the court could have acknowledged that the state law does not directly resolve the question. Because implied preemption is forbidden, the local ordinance would stand, an act of respect for the sovereign people’s decision to vest regulating power in their local government.
At all levels, governments face a panoply of pressing policy questions: climate change, immigration, abortion access, affordable housing. Cities are often on the frontlines.168 And with dysfunction at the state and national levels, local governments are left with much of the responsibility for addressing these challenges.169
Implied preemption undermines cities’ capacity to dynamically respond. Imperium urbis is a roadmap to help cities navigate the morass: by invoking popular sovereignty, litigants can encourage courts to favor cities in local-state preemption disputes. Alone, it will not resolve all the issues facing local governments, but it arms cities with a doctrinal tool to start tackling them.