Amicus Curiae Brief — Suncor Energy (U.S.A.) Inc., et al., Petitioners v. County Commissioners of Boulder County, et al.

No. 25-170

In the Supreme Court of the United States

________________

SUNCOR ENERGY (U.S.A.) INC., ET AL.,

Petitioners,

v.

COUNTY COMMISSIONERS OF BOULDER COUNTY, ET

AL.,

Respondents.

________________

On Writ of Certiorari to the

Supreme Court of Colorado

________________

BRIEF FOR AMICI CURIAE ASSOCIATED GOVERNMENTS OF NORTHWEST COLORADO, ARCHULETA

COUNTY, DELTA COUNTY, GRAND COUNTY, GARFIELD COUNTY, MESA COUNTY, MONTEZUMA

COUNTY, MONTROSE COUNTY, AND RIO BLANCO

COUNTY

IN SUPPORT OF PETITIONERS

________________

Mark M. Rothrock

Katherine C. Yarger

LEHOTSKY KELLER COHN LLP

Counsel of Record

8513 Caldbeck Drive

LEHOTSKY KELLER COHN LLP

Raleigh, NC 27615

700 Colorado Blvd., #407

Denver, CO 80206

(303) 717-4749

katie@lkcfirm.com

Counsel for Amici Curiae

TABLE OF CONTENTS

Interest of Amici Curiae ............................................. 1

Introduction and Summary of Argument .................. 4

Argument .................................................................... 7

I.

Litigation like administrative adjudication

can serve as a regulatory tool. ............................ 9

II. One county may not impose its policy

preferences on sister counties through tort

litigation............................................................. 12

Conclusion................................................................. 17

(i)

ii

TABLE OF AUTHORITIES

Page(s)

Cases

Benewah Cnty. Cattleman’s Ass’n, Inc. v.

Bd. of Cnty. Comm’rs of Benewah

Cnty.,

668 P.2d 85 (Idaho 1983) ..................................... 13

BMW of N. Am., Inc. v. Gore,

517 U.S. 559 (1996) .............................................. 10

Cedar Cnty. Comm’n v. Parson,

661 S.W.3d 766 (Mo. 2023) .................................. 12

Cipollone v. Liggett Grp., Inc.,

505 U.S. 504 (1992) .............................................. 10

City of Longmont v. Colo. Oil & Gas

Ass’n,

369 P.3d 573 (Colo. 2016)............................... 14, 16

Colo. Min. Ass’n v. Bd. of Cnty.

Comm’rs,

199 P.3d 718 (Colo. 2009)........................... 4, 13, 15

Craig v. Cnty. of Chatham,

565 S.E.2d 172 (N.C. 2002) .................................. 12

Dill v. Bd. of Cnty. Comm’rs.,

928 P.2d 809 (Colo. Ct. App. 1996) ...................... 13

Gonzalez v. Ideal Tile Importing Co.,

853 A.2d 298 (N.J. Super. Ct. App.

Div. 2004) ............................................................. 11

Laramie Cnty. Comm’rs v. Albany Cnty.

Comm’rs,

92 U.S. 307 (1875) ................................................ 12

iii

State ex rel. Morrison v. Beck Energy

Corp.,

37 N.E.3d 128 (Ohio 2015) ............................. 13, 16

Palmer v. Liggett Grp., Inc.,

825 F.2d 620 (1st Cir. 1987)................................. 11

San Diego Bldg. Trades Council v.

Garmon,

359 U.S. 236 (1959) .................................... 9, 10, 12

State ex rel. Village of Los Ranchos de

Albuquerque v. City of Albuquerque,

889 P.2d 185 (N.M. 1994)..................................... 13

Voss v. Lundvall Bros., Inc.,

830 P.2d 1061 (Colo. 1992)................................... 16

Wood v. Gen. Motors Corp.,

865 F.2d 395 (1st Cir. 1988)................................. 11

Other Authorities

Boulder Chamber Economic Council,

Key Industries and Companies,

https://perma.cc/8LZW-B2Y8 ................................. 5

Colo. Dep’t of Local Affairs, Fifty-Fourth

Annual Report of the Division of

Property Taxation,

https://perma.cc/5WGE-5HYK ........................... 5, 6

Colo. Energy & Carbon Mgmt. Comm’n,

Active Well Count by County and

Year Report, https://perma.cc/3YLMH5RN .................................................................. 5, 6

Colo. Energy & Carbon Mgmt. Comm’n,

Production by County,

https://perma.cc/A58E-3Q25 .............................. 5, 6

iv

Colo. Geological Survey, IS-88 Colorado

Mineral and Energy Industry

Activities 2024-2025,

https://perma.cc/CX92-EP2H ................................. 6

Delta County, Largest Employers in

Delta County,

https://perma.cc/L9VN-NM7S; .............................. 6

U.S. Census Bureau, Quick Facts:

Archuleta County, Colorado,

https://perma.cc/4NE8-E23U ................................. 6

U.S. Census Bureau, Quick Facts:

Boulder County, Colorado,

https://perma.cc/4YX2-PQ8W ................................ 4

U.S. Census Bureau, Quick Facts:

Garfield County, Colorado,

https://perma.cc/2WGA-4GYN; .............................. 5

U.S. Census Bureau, Quick Facts: Rio

Blanco County, Colorado,

https://perma.cc/82B7-BL3D.................................. 5

INTEREST OF AMICI CURIAE

Amicus Curiae1 Associated Governments of

Northwest Colorado (“AGNC”) is a statutory local government organized as the Council of Governments and

federally designated Economic Development District

serving counties in northwest Colorado, with associate-member counties in Colorado’s Western Slope.

AGNC’s mission is to advocate, inform, and reflect the

needs of its members and promote the values, industries, and economies of Northwest Colorado. AGNC

serves as a regional convener and nonpartisan advocate for rural local governments whose communities

depend on a stable energy economy, and whose budgets, public services, and residents are directly affected

when disruptions in regional energy markets increase

costs or erode local tax revenues. AGNC has a direct

interest in ensuring that state tort law claims premised on the cumulative effects of global greenhouse-gas

emissions do not expose that economic foundation to

open-ended, multi-jurisdictional liability that would

threaten the stability of member county economies.

AGNC’s interest is specific to the unique legal context

presented in this case and does not extend to any argument that state tort remedies should be limited in

cases involving direct and identifiable sources of

harm.

Archuleta, Delta, Garfield, Mesa, Montrose,

1 Pursuant to Supreme Court Rule 37.6, amicus curiae states

that no counsel for any party authored this brief in whole or in

part and no entity or person, aside from amicus curiae, its

members, or its counsel, made any monetary contribution

intended to fund the preparation or submission of this brief.

(1)

2

Montezuma, and Rio Blanco Counties are statutory

counties located in Colorado’s Western Slope whose

tax bases and economies depend substantially on energy production and related industries. These Counties and their residents rely on that sector for significant financial support, including severance tax distributions, federal mineral lease and royalty revenues,

property taxes on energy infrastructure, and energysector employment. Garfield County, for instance, is

Colorado's second-leading natural gas producer and

sits atop the second-largest producible shale basin in

North America. And in Montezuma County, between

40 and 50 percent of county tax revenue has historically come from oil and gas production.

These Counties have a direct interest in the legal

framework governing liability for the cumulative effects of greenhouse-gas emissions and in ensuring that

the voices reaching this Court from Colorado's political subdivisions reflect the State’s full geographic and

economic diversity. The potential impacts of this litigation on these Counties are staggering, particularly

compared to Respondents Boulder County and the

City of Boulder, which are located half a state away on

Colorado’s Front Range. Respondents’ litigation tactics discourage continued domestic energy production

and investment, threatening these Counties’ rural

economies and their ability to fund roads, schools,

emergency services, and other critical public functions. At bottom, Respondents’ political and economic

priorities differ substantially from those of these

Counties, and Respondents do not speak for Delta,

Garfield, Mesa, Montrose, Montezuma, and Rio

3

Blanco Counties on the questions presented here.

Grand County is a statutory county located in Colorado’s North Central mountains. It is home to the

headwaters of the Colorado River, whose streams and

rivers provide water to communities and agricultural

operations throughout the West. Situated at the west

entrance to Rocky Mountain National Park, Grand

County’s economy is built on tourism and year-round

outdoor recreation, including skiing, boating and fishing on its many lakes, and rafting and fly-fishing on

the Colorado River. These attractions draw over 7.7

million visitors a year.

Grand County has a direct governmental interest

in the legal framework governing liability for the cumulative effects of greenhouse-gas emissions, and in

ensuring that the political subdivisions whose voices

reach this Court reflect Colorado’s full geographic and

economic diversity. Colorado’s system of local government rests on the principle that each county and municipality governs according to the needs and priorities of its own residents—not those of its neighbors.

Whatever policy choices Boulder County and the City

of Boulder have made for their own communities,

those choices do not bind Grand County. Respondents

have no authority to pursue litigation that would effectively impose their political and economic preferences on other Colorado jurisdictions. Boulder County

and the City of Boulder do not speak for Grand County

on the questions presented here.

4

INTRODUCTION AND SUMMARY OF ARGUMENT

Respondents seek to impose their energy policy

preferences not only across the nation and the globe,

but also upon sister counties in the State of Colorado.

Along with the interstate and foreign-affairs concerns

Petitioners have raised, this intrastate conflict only

strengthens the conclusion that the Colorado Supreme

Court erred in allowing this case to proceed. Amici

write separately to draw this Court’s attention to this

intrastate dimension: Respondents are attempting to

wield the adjudicatory process as a regulatory instrument, not merely against out-of-state and international actors, but against the interests of sister counties in Colorado.

Along with Boulder County, Amici are statutory

counties that are political subdivisions of the same

sovereign—Colorado—whose law Respondents invoke

in this litigation. See Colo. Mining Ass’n v. Bd. of Cnty.

Comm’rs, 199 P.3d 718, 729 (Colo. 2009) (en banc). But

while Boulder County and Amici stand on equal footing within Colorado’s political structure, they have different constituencies and possess vastly different economic interests.

Relevant here, there is a striking contrast between Respondents’ and Amici’s economic reliance

upon the fossil fuel industry. Boulder County is one of

Colorado’s most populous jurisdictions, with approximately 330,000 residents concentrated in an urban

core anchored by a major research university.2 Its

See U.S. Census Bureau, Quick Facts: Boulder County,

Colorado, https://perma.cc/4YX2-PQ8W.

2

5

economy is driven by technology, aerospace, and

higher education.3 Amici’s counties are different not

only in the density of their population but in the very

nature of their industries. For instance, Garfield

County, with roughly 60,000 residents spread across

the Colorado River corridor, hosts 12,027 active oil and

gas wells and produced over 307 million thousand-cubic feet (“MCF”) of natural gas in 2025 alone, with taxable oil and gas assets valued at more than $1.3 billion.4 Rio Blanco County—home to fewer than 7,000

people—produced over 3.2 million barrels of oil and

more than 85 million MCF of natural gas in 2025, with

assessed oil and gas valuation exceeding $405 million.5 Similarly, Archuleta County, in southwestern

Colorado, is home to just over 14,000 residents, and

produced over 21 million MCF of natural gas in 2025,

3 See Boulder Chamber Economic Council, Key Industries and

Companies, https://perma.cc/8LZW-B2Y8.

See U.S. Census Bureau, Quick Facts: Garfield County,

Colorado, https://perma.cc/2WGA-4GYN; Colo. Energy & Carbon

Mgmt. Comm’n, Active Well Count by County and Year Report,

https://perma.cc/3YLM-H5RN (“Well Report”); Colo. Energy &

Carbon

Mgmt.

Comm’n,

Production

by

County,

https://perma.cc/A58E-3Q25 (“2025 Production Report”); Colo.

Dep’t of Local Affairs, Fifty-Fourth Annual Report of the Division

of Property Taxation at 196-97, https://perma.cc/5WGE-5HYK

(“Property Taxation Report”).

4

5 See U.S. Census Bureau, Quick Facts: Rio Blanco County,

Colorado, https://perma.cc/82B7-BL3D; 2025 Production Report;

Property Taxation Report at 196-97.

6

with oil and gas valuations of in excess of $36 million.6

Mesa County, the regional hub of western Colorado,

operates 1,178 active wells and carries oil and gas valuations of approximately $140 million.7 And Delta

County is home to many of the employees of the West

Elk Mine—the state’s largest coal operation—and

therefore derives a primary share of its employment

and tax base from coal mining.8 These are not abstract

statistics. They represent the basis for tax revenues

that fund county roads, schools, emergency services,

and public health infrastructure across communities.

If Respondents’ regulatory tactics lead to a contraction

of the fossil fuel economy, critical public funds will diminish too.

A damages award of the magnitude Respondents

seek would depress investment, constrain production,

and reduce the assessed valuations upon which Amici

and their neighbors rely to fund the basic functions of

local government. Respondents, with their minimal

fossil fuel footprint and diversified urban economy,

bear virtually none of that exposure. The Amici bear

nearly all of it.

A single county, acting through litigation and

U.S. Census Bureau, Quick Facts: Archuleta County,

Colorado, https://perma.cc/4NE8-E23U; 2025 Production Report;

Property Taxation Report at 196-97.

6

7 See Well Report; 2025 Production Report; Property Taxation

Report at 196-97.

See Delta County, Largest Employers in Delta County,

https://perma.cc/L9VN-NM7S; Colo. Geological Survey, IS-88

Colorado Mineral and Energy Industry Activities 2024-2025 at

14, https://perma.cc/CX92-EP2H.

8

7

insulated from the costs it seeks to impose, should not

be permitted to set energy policy for the communities

most directly affected by that policy. Along with the

interstate and foreign-affairs concerns raised by Petitioners, this intrastate dimension only strengthens

the case for reversal of the Colorado Supreme Court’s

decision.

ARGUMENT

Respondents seek to use state tort claims to regulate a fundamentally global phenomenon: greenhousegas emissions and their alleged effects on the earth’s

climate. As Petitioners explain, the Constitution does

not permit a single locality to impose tort liability for

harms allegedly caused by the worldwide production

and use of fossil fuel activity generating emissions

arising across the globe. Such claims intrude upon an

area reserved to federal law because greenhouse-gas

emissions transcend borders of any kind, implicate

competing sovereign interests, and require nationally

uniform rules.

This Court’s precedents have long recognized interstate pollution disputes as matters governed exclusively by federal law. Although Congress displaced

federal common law through enactment of the Clean

Air Act, Congress did not authorize local counties to

impose their own claimed solution to a global phenomenon by invocation of state tort regimes. This approach is impermissibly extraterritorial. Respondents

seek damages for injuries that cannot be confined to

city or county borders as the activities and attendant

phenomena occur worldwide. Allowing such claims to

proceed would effectively permit each State and, as

8

relevant to these Amici, each locality within a State to

attempt to dictate national climate and energy policy,

creating conflicting legal standards, massive and duplicative liability, and substantial disruption to one of

the Nation’s largest and most important industries.

Petitioners correctly warn that, if sustained, the decision below would invite courts and juries nationwide

to establish climate policy through state tort law rather than through the political branches of the federal

government.

This is all the more significant given the federal

government’s exclusive authority over foreign affairs.

Because climate change and greenhouse-gas emissions are inherently global issues that implicate international diplomacy, trade, energy security, and treaty

negotiations, state-law tort suits targeting worldwide

emissions threaten to undermine the federal government’s carefully calibrated foreign-policy judgments.

The Constitution entrusts such matters exclusively to

the national government and therefore precludes

state-law claims predicated on international emissions and global policy.

Finally, Petitioners are correct that the Clean Air

Act independently preempts Respondents’ claims. The

Clean Air Act conflicts with state-law efforts to impose

liability for out-of-state emissions. By empowering

EPA to establish nationwide standards and by creating specific mechanisms for interstate pollution disputes and oversight, Congress foreclosed the use of

state tort law as an alternative regulatory mechanism.

9

*

*

*

Petitioners correctly explain why Respondents’

claims are incompatible with federal authority over interstate pollution. Amici’s arguments highlight an additional dimension—the intrastate consequences of

permitting local counties, through the tool of tort litigation, to impose economic and policy consequences

borne disproportionately by sister counties possessing

equal political status. Respondents should not be permitted to impose their policy preferences onto coordinate political subdivisions with fundamentally different economic interests and governing priorities.

I.

Litigation like administrative adjudication

can serve as a regulatory tool.

Respondents here do not merely seek

“compensation” for harms caused within their

jurisdictional borders. Instead, they seek to regulate a

worldwide industry. This Court has recognized that

common-law litigation may operate as a form of

regulation no less than legislation or administrative

action.

The foundational decision is San Diego Building

Trades Council v. Garmon, 359 U.S. 236 (1959). There,

the Court explained that “regulation can be as

effectively exerted through an award of damages as

through some form of preventive relief. The obligation

to pay compensation can be, indeed is designed to be,

a potent method of governing conduct and controlling

policy.” Id. at 247. As a result, state tort litigation

implicates the same supremacy, equal sovereignty,

and uniformity concerns as direct governmental

10

regulation. Indeed, in Garmon, the Court rejected any

formal distinction between regulation accomplished

through

agency

commands

and

regulation

accomplished through liability imposed by courts and

juries. “[R]emedies,” the Court explained, “form an

ingredient of any integrated scheme of regulation.” Id.

This Court has repeatedly reaffirmed that

principle. In Cipollone v. Liggett Group, Inc., the

plurality held that state common-law tort claims could

constitute state-law “requirements or prohibitions”

subject to federal preemption. 505 U.S. 504, 522 (1992)

(citation modified). Quoting Garmon, this Court

reiterated that “regulation can be as effectively

exerted through an award of damages as through

some form of preventive relief.” Id. at 521 (citation

modified). The plurality further recognized that tort

suits necessarily rest upon state-imposed legal duties

and therefore function as regulatory commands:

“common-law damages actions . . . are premised on the

existence of a legal duty, and it is difficult to say that

such actions do not impose ‘requirements or

prohibitions.’” Id. at 522 (citation omitted). A tort

verdict, no less than a statute, directs future conduct

by attaching legal consequences to disfavored

behavior. Likewise, in BMW of North America, Inc. v.

Gore, the Court again emphasized that “[s]tate power

may be exercised as much by a jury’s application of a

state rule of law in a civil lawsuit as by a statute.” 517

U.S. 559, 572 n.17 (1996).

Lower federal courts and state courts have

similarly noted this principle. In Palmer v. Liggett

Group, Inc., the First Circuit observed that a verdict

11

in a cigarette-warning label suit would “arrogate[] to

a single jury the regulatory power explicitly denied to

all fifty states’ legislative bodies.” 825 F.2d 620, 628

(1st Cir. 1987). This is because a damages award has

“an effect similar to . . . a state regulation”—it exerts

regulatory force over future conduct. Wood v. Gen.

Motors Corp., 865 F.2d 395, 408 (1st Cir. 1988); see

also Gonzalez v. Ideal Tile Importing Co., 853 A.2d

298, 305 n.4 (N.J. Super. Ct. App. Div. 2004) (noting

that “[t]he obligation to pay compensation can be,

indeed is designed to be, a potent method of governing

conduct and controlling policy” (citation modified)).

The logic of those observations applies with great

force here. A climate-change tort judgment would not

merely compensate discrete injuries; it would operate

as a de facto emissions and energy policy, compelling

companies to alter nationwide—and indeed

worldwide—production, marketing, and investment

decisions under threat of massive liability.

That regulatory objective is not incidental to

Respondents’ lawsuit; it is its premise. Respondents

do not allege, nor could they, that Petitioners caused

localized pollution confined within state borders. They

seek to hold Petitioners liable for the cumulative

effects of worldwide greenhouse-gas emissions

resulting from the extraction, sale, and combustion of

fossil fuels across the globe over many decades. The

relief sought is correspondingly regulatory in

character. Massive compensatory and punitive

damages tied to the societal costs of climate change

would necessarily function as a judicially imposed

carbon-pricing regime—one fashioned not by Congress

12

or federal agencies, but by state juries applying

divergent standards in jurisdictions across the

country.

Permitting such suits would authorize each State,

and indeed each locality, to superimpose its own policy

judgments onto a matter of uniquely national and

international concern. One jury might conclude that

lawful fossil-fuel production should carry billions of

dollars in liability; another might not. Some

jurisdictions might effectively demand rapid

decarbonization; others might tolerate continued

production. The resulting patchwork would subject

national energy policy to untenable extraterritorial

control.

Because “[t]he obligation to pay compensation” is

“a potent method of governing conduct and controlling

policy,” Garmon, 359 U.S. at 247, these actions cannot

be dismissed as ordinary compensation litigation.

They are exercises of sovereign regulatory power

through the vehicle of tort law.

II. One county may not impose its policy

preferences on sister counties through tort

litigation.

Courts across the country agree on the

foundational principle that a county’s regulatory

authority ends at its own borders. County

governments derive their existence from state law,

and any exercise of regulatory power requires

affirmative authorization from the state. See, e.g.,

Laramie Cnty. Comm’rs v. Albany Cnty. Comm’rs, 92

U.S. 307, 312 (1875); Cedar Cnty. Comm’n v. Parson,

13

661 S.W.3d 766, 771-72 (Mo. 2023) (en banc); Craig v.

Cnty. of Chatham, 565 S.E.2d 172, 175 (N.C. 2002).

Thus, the “basic rule is that a local government has no

extraterritorial powers and cannot, without express

authorization from the state, extend its regulations or

the force of its laws outside its own boundaries.” State

ex rel. Village of Los Ranchos de Albuquerque v. City

of Albuquerque, 889 P.2d 185, 195 (N.M. 1994)

(citation omitted); see Benewah Cnty. Cattleman’s

Ass’n, Inc. v. Bd. of Cnty. Comm’rs of Benewah Cnty.,

668 P.2d 85, 88 (Idaho 1983) (explaining that a county

“ordinance is without force and effect within the

limits” of other political subdivisions of the state).

Within this framework, a county’s regulatory power

generally extends only to “matters which are strictly

local and do not impinge upon matters which are of a

state-wide nature or interest.” State ex rel. Morrison v.

Beck Energy Corp., 37 N.E.3d 128, 133-34 (Ohio 2015)

(citation modified).

Colorado applies the same principles. Statutory

counties “derive their authority from the state” and

“possess only those authorities expressly conferred

upon them by the state and those incidental implied

powers reasonably necessary to carry out their

expressly granted powers.” Colo. Min. Ass’n, 199 P.3d

at 729. Indeed, a statutory county “has no inherent

sovereign authority.” Dill v. Bd. of Cnty. Comm’rs, 928

P.2d 809, 812 (Colo. Ct. App. 1996). Colorado courts

thus weigh several factors to determine the validity of

a political subdivision’s regulatory actions, including

“(1) the need for statewide uniformity of regulation, (2)

the extraterritorial impact of the local regulation, (3)

14

whether the state or local governments have

traditionally regulated the matter, and (4) whether

the Colorado Constitution specifically commits the

matter to either state or local regulation.” City of

Longmont v. Colo. Oil & Gas Ass’n, 369 P.3d 573, 580

(Colo. 2016). Even for home-rule political subdivisions

that possess greater regulatory authority than

statutory counties, where a local action generates a

“ripple effect that impacts state residents” outside the

enacting jurisdiction with “serious consequences,”

that impact will weigh decisively in favor of finding

the regulatory action invalid. Id. at 581 (citation

omitted). A principal aim of this approach is to avoid

“creating a patchwork of local and state rules” and to

prevent political subdivisions from enacting “de facto

statewide” regulations. Id. (citation omitted).

As a result, this case also presents a foundational

question about the proper role of local governments

within a single sovereign State. Respondents seek to

invoke Colorado law not simply to obtain

compensation for localized harms, but to impose policy

consequences that will be borne disproportionately by

other counties possessing equal legal status under

Colorado law. In practical effect, Respondents seek to

leverage the judicial process to accomplish what they

could not accomplish through the ordinary political

process: the imposition of a statewide energy policy

preference favoring rapid contraction of fossil-fuel

production and use.

But Colorado’s sister counties are not subordinate

policy enclaves whose economic futures may be

dictated by whichever locality is most politically

15

opposed to a particular industry. Boulder County is

not Colorado’s energy overlord. It is not authorized to

use tort law as a mechanism for restructuring the

State’s economy according to Boulder County’s own

policy preferences while externalizing the resulting

costs onto other communities. Colorado’s statutory

counties stand on equal footing as political

subdivisions of the State. See Colo. Min. Ass’n, 199

P.3d at 729. They serve different constituencies,

possess different economies, and necessarily adopt

different policy priorities in response to local

conditions and needs. See supra. pp. 4-6 (describing

how Respondents’ economic interests diverge sharply

from those of Amici). What may appear economically

inconsequential to Boulder County may threaten the

fiscal stability of rural counties whose schools, roads,

hospitals,

and

emergency

services

depend

substantially upon energy development and mineral

production. See id.

That divergence of interests matters here because

Respondents’ theory of liability is inherently

regulatory in operation. The extraordinary damages

Respondents seek would not remain confined to

Boulder County. Any judgment of the magnitude

contemplated by this litigation would predictably alter

investment decisions, suppress production activity,

increase operational costs, and diminish the tax base

upon which energy-producing counties depend. Those

consequences would radiate throughout Colorado’s

rural communities irrespective of whether those

communities agree with Respondents’ policy

objectives. Respondents thus seek to impose statewide

16

and indeed global economic and policy consequences

through the adjudicative process even though

Colorado’s political structure provides no authority for

one county to regulate the economic priorities of

another.

The concern is not merely economic. Colorado’s

constitutional structure reflects a balance between

statewide interests and local self-government.

Allowing one locality to wield state tort law as a de

facto instrument of statewide energy regulation would

destabilize that balance by empowering individual

counties to pursue conflicting statewide agendas

through litigation. But courts in Colorado and across

the country have recognized that county and local

governments do not have the power to regulate

issues—like this one—that are of statewide concern.

See, e.g., Voss v. Lundvall Bros., Inc., 830 P.2d 1061,

1062 (Colo. 1992) (en banc) (explaining that the

“efficient development and production of oil and gas

resources” was a matter of “statewide interest”); Beck

Energy Corp., 37 N.E.3d at 133-34 (explaining that

local governments in Ohio may not regulate “matters

which are of a statewide nature or interest”). Thus, in

similar circumstances, state courts have struck down

“de facto statewide” regulations based in part on the

need to avoid “creating a patchwork of local and state

rules.” See, e.g., City of Longmont, 369 P.3d at 581.

Respondents’ litigation tactics are of a kind with such

impermissible attempts to dictate statewide policy.

Today the issue is fossil-fuel production,

tomorrow it could be water or transportation. If each

locality may deploy tort law to impose its own

17

preferred statewide policy outcomes on sister counties,

the result will be fragmentation, instability, and

precisely the kind of patchwork governance this Court

and Colorado courts alike have repeatedly rejected.

Amici do not contend that state tort law is

categorically unavailable whenever interstate or

statewide economic effects are present. Nor do Amici

dispute that counties may seek relief for genuinely

localized harms occurring within their own

jurisdictional boundaries. The problem here is the

unprecedented attempt to use state-law tort theories

to regulate a global industry and thereby impose

sweeping economic consequences upon coordinate

political subdivisions that reject Respondents’ policy

judgments. The Constitution does not permit one

county to exercise that kind of regulatory authority

over the rest of the State through the vehicle of tort

litigation.

CONCLUSION

The judgment of the Colorado Supreme Court

should be reversed.

18

Respectfully submitted,

KATHERINE C. YARGER

Counsel of Record

LEHOTSKY KELLER COHN LLP

700 Colorado Blvd., #407

Denver, CO 80206

(303) 717-4749

katie@lkcfirm.com

MARK M. ROTHROCK

LEHOTSKY KELLER COHN LLP

8513 Caldbeck Drive

Raleigh, NC 27615

Counsel for Amici Curiae

MAY 2026