Boulder's climate case is 3,093 days old and a tie would send it to trial

The Supreme Court heard Suncor Energy v. County Commissioners of Boulder County on 5 October, the first argument of the term. Suncor v. Boulder asks whether a city can use state tort law against the companies that sold the fuel. Boulder filed the suit on 17 April 2018, which makes it 3,093 days old before any trial has started. Suncor and ExxonMobil want federal law to preclude the state claims. Around 60 state and local governments are waiting on the answer.

“Everybody agrees that state tort law is a form of regulation”

— Эми Кони Барретт, Судья Верховного суда США, слушание 5 октября 2026

A tie affirms the court below

Justice Alito recused himself on 28 September, seven days before argument, leaving eight. A 4-4 split affirms the Colorado Supreme Court, which already ruled 5-2 against preemption. For Boulder, a deadlocked court is a win and the case goes back toward trial.

Alejandro Camacho's recap for Legal Planet reads Sotomayor, Jackson and Kagan as leaning toward Boulder, with Kavanaugh, Roberts and Barrett toward the companies, and Gorsuch and Thomas unplaced. That is three and three with two unplaced, on a bench where a tie favours the side that won below.

The statute the argument rests on just got smaller

Kavanaugh told the room that interstate air and water pollution are matters for federal law unless Congress specifically preserves state law, and warned that suits like Boulder's could bankrupt defendants.

The complication is the EPA. Barrett raised the agency's recent position that the Clean Air Act does not authorise regulating greenhouse gases from motor vehicles. Camacho's reading of her point: if the Act no longer displaces federal common law, the question reverts to federal common law, and a federal court could then decide there is no cause of action at all.

The companies lose the statute they were relying on and gain a different route to the same dismissal.

The clock on the case

Exxon and Suncor filed for certiorari on 8 August 2025. The Court granted it 199 days later and heard argument 224 days after that. Boulder's case is now 1.94 times longer than the SEC's suit against Ripple, which we counted at 1,598 days when its author was named for a White House role.

Camacho also notes the argument nobody made. Boulder did not press the line of cases where the Court let state tort claims stand alongside federal regulation, in nuclear power, tobacco and pesticides. The foreign-affairs framing that filled the pre-argument commentary drew no questions. For crypto the link runs through the oil price, where we measured a 0.68 correlation on 28 September; a liability ruling against the majors would move that input before it moves bitcoin.

Informational material, not investment advice. The Court has not ruled, and the readings of how individual justices leaned come from one published recap of the argument.