Boulder’s lawyer said its theory does not rule out claims against large retailers, while identifying legal limits such a claim would still face. The Supreme Court is also deciding whether it has jurisdiction to hear the case at all.
On October 5, 2026, in Washington, Justice Thomas asked Kevin K. Russell, Boulder’s lawyer, whether its climate theory could reach large retailers. The Supreme Court’s official argument transcript records the exchange in *Suncor Energy (U.S.A.) Inc. v. County Commissioners of Boulder County*, No. 25-170. During oral argument, Russell answered: “Nothing in our theory prevents that.” (87:7-8.) Kannon K. Shanmugam, arguing for the petitioners, told the Court that plaintiffs seek billions of dollars in each of these cases. The justices must now decide whether federal law stops Boulder’s state-law claims, or whether they can decide that question at all.
Thomas began by asking whether Russell had “a limiting principle” for whom Boulder could sue. Russell identified limits on the choice of state law, interstate commerce and personal jurisdiction. Thomas then asked whether Boulder could “just as easily sue large retailers of” the products at issue. Russell said he thought nothing in the Constitution would prevent it. When Thomas narrowed the question to Boulder’s own theory, Russell gave the answer that made the exchange consequential: nothing in that theory prevents it. (86:9-87:8.)
The 3 sources behind this story: 3 court records, each linked with what it shows. Free with the weekly Litigation Sentinel brief.
Russell did not say a retailer would be liable. He immediately added that Colorado courts might reach a different conclusion under state tort law. Later, he said Boulder would have to establish a sufficient causal connection between the alleged conduct and injury, an element he acknowledged the petitioners say Boulder cannot prove. (87:8-21; 95:18-96:2.) The distinction left Thomas’s question alive: a potential defendant may fall within the theory even if a particular claim against it fails.
That was a wider answer than the case caption suggests. The Supreme Court docket names Suncor Energy (U.S.A.) Inc. and other petitioners against the County Commissioners of Boulder County and other respondents. The argument moved beyond those parties when Thomas tested the boundary of the county’s proposed claims. No retailer was found liable in this exchange.
Shanmugam described Boulder’s claims as an attempt to use Colorado law to govern conduct and emissions extending far beyond the state. He argued that federal law governs interstate pollution claims, a principle he said applies with even greater force to claims involving global climate change. The question presented to the Court asks whether federal law precludes state-law claims seeking relief for injuries allegedly caused by the effects of interstate and international greenhouse-gas emissions on the global climate.
Free weekly intelligence for executives responsible for litigation exposure: the named decision-makers, dollar exposure, operating consequence, and next development.
Russell gave the justices a different account. He argued that states can provide remedies for injuries within their borders even when the conduct alleged to have caused them occurred elsewhere. He characterized Boulder’s claims as including alleged deception by defendants he described as non-emitters. When Chief Justice Roberts asked whether Boulder’s suit was an attempt to evade earlier decisions concerning emissions, Russell denied that its deception theory sought to reduce emissions. Under that theory, he said, producers could continue producing fossil fuels if consumers were properly informed about the consequences. (84:8-86:3; 96:10-97:19.)
The money entered the argument when Justice Jackson asked why the Court should take up the issue while other federal defenses remained before the state court. Shanmugam said the petitioners faced claims from more than 60 municipalities in around three dozen cases. He said plaintiffs sought billions of dollars in each case and argued for an answer now. Earlier, he warned that, if Boulder’s claims proceed, some 90,000 municipalities could ask juries for damages. Those figures were counsel’s account and forecast, not findings by the Court. (54:1-55:17; 6:1-6.)
*Analysis:* For a large retailer, Thomas’s exchange exposed a possible path to litigation spend and trial risk under Boulder’s theory, while Russell’s answers left the outcome of any such claim to state tort law, causation and other limits. The argument established neither a claim against a retailer nor a dollar amount for one.
The case may end before the justices settle the federal-law question. When the Court granted review, it also directed the parties to argue whether it has statutory and Article III jurisdiction to hear this case. Russell argued that the petitioners had “failed to establish” the Court’s jurisdiction to hear what he called “this interlocutory appeal.” Justice Jackson pressed Shanmugam on why the Court should hear the preclusion question separately while other federal issues were still in state court. (86:4-7; 53:21-54:18.)
The docket records that the Supreme Court of Colorado decided the lower-court matter on May 12, 2025. It also records the October 5 argument and a September 28 letter stating that Justice Alito would no longer participate. The docket lists no dated next event or decision.
Thomas asked where Boulder’s theory stops. Russell answered that it does not itself stop at the producers named in this case, then pointed to other legal limits. The next ruling could decide whether federal law shuts the claims down, lets them continue, or whether the Supreme Court lacks jurisdiction to answer yet. Until the Court rules, the retailer exchange sits on pages 86 and 87 of the transcript.
The Executive Briefing has five questions about your reported litigation practices. Use the summary to choose an operating question to explore.
Take the Executive Briefing →Free weekly intelligence for executives responsible for litigation exposure: the named decision-makers, dollar exposure, operating consequence, and next development.