Harriet Hageman, Wyoming's congresswoman and a candidate for U.S. Senate, has a new project: making it harder for states to protect their people from dirty air. And the people cheering her on are exactly the ones you'd expect — Big Oil.

What she did

On July 18, Hageman introduced a resolution under the Congressional Review Act to revoke California's Clean Air Act waiver for greenhouse gas standards on cars — the EPA decision, first granted in 2009, that lets the state enforce stronger-than-federal limits on the greenhouse gases coming out of new vehicles, according to the Sierra Club. Those waivers matter far beyond California, because other states are allowed to follow California's cleaner standards instead of the weaker federal ones.

These standards are already fully phased in, the Sierra Club notes — the cars and trucks built to them are already on the road. Killing the waiver now is about tearing down protections that are working.

The Sierra Club didn't hold back. "Congressional Republicans and the Trump administration are once again putting Big Oil's profits ahead of Americans' health and wallets," said Patrick Drupp, the group's climate policy director. He noted that California's waivers "have delivered cleaner air, driven innovation, and saved drivers money for decades," and that gutting them "will not make cars more affordable."

Who Hageman actually works for

To understand why Hageman would spend her time attacking clean-air rules, follow the money.

Hageman works for the fossil fuel industry. She sits on the House Natural Resources Committee and chairs its Water, Wildlife and Fisheries Subcommittee — and among the corporate PACs that have given her the most are coal giant Peabody Energy, Koch, and the refiner HF Sinclair. Wyoming is the biggest coal-producing state in the country, and Hageman has built her career defending the industries that dig it up and burn it.

Her environmental record is about as bad as it gets. She scored a 0% from the League of Conservation Voters in 2025, and a 1% lifetime score. In other words, on nearly every vote that pit clean air, clean water, or public lands against polluters, Hageman sided with the polluters.

This resolution is just the latest example: she chairs a subcommittee meant to protect natural resources, and she's using her seat in Congress to tear down protections instead.

Cleaner air is the thing on the chopping block

Let's be clear about what's at stake. The waiver Hageman wants to kill covers greenhouse gases from cars and trucks — one piece of the set of clean-car rules that states have used for decades to cut what comes out of the tailpipe. The whole point of California's standards — and the states that follow them — is to cut that pollution and push automakers to build cleaner, cheaper-to-run vehicles.

Hageman calls them "burdensome regulations." The families breathing the air might call them lifesaving.

The bottom line

Hageman wants to be Wyoming's next senator. This is a preview of the kind of senator she'd be: one who takes fossil-fuel money, chairs a subcommittee that oversees the country's water and wildlife, and uses her seat to help her donors pollute more freely — while claiming that California's rules are what "raises costs for consumers."

The oil industry's profits are safe with Harriet Hageman. Your lungs are the thing she's willing to trade away.

Source

• "Sierra Club Condemns Congressional Effort to Attack California's Waivers Protecting Clean Air," Sierra Club, July 20, 2026.