In the wake of the Trump administration’s announcement that it will overturn the rule which underpins virtually all US climate regulations, a Senate committee has launched an investigation into a suspected lobbying push that led to the move.
On Tuesday, the Senate environment and public works committee sent letters to two dozen corporations, including oil giants, thinktanks, law firms and trade associations. The missives request each company to turn over documents regarding the 2009 declaration, known as the endangerment finding, which the Environmental Protection Agency (EPA) said in July that it will unmake.
The finding enshrined that carbon dioxide and five other greenhouse gases harm the health of Americans.
“Rescinding the endangerment finding at the behest of industry is irresponsible, legally dubious, and deeply out of step with the EPA’s core mission of protecting human health and the environment, and the American public deserves to understand your role in advancing EPA’s dangerous decision,” wrote Rhode Island senator Sheldon Whitehouse, the ranking member of the committee. “I am concerned about the role that fossil fuel companies, certain manufacturers, trade associations, polluter-backed groups, and others with much to benefit from the repeal of the endangerment finding – including your organization – played in drafting, preparing, promoting, and lobbying on the proposal.”
Fossil fuel companies and their allies are threatened by the endangerment finding because it confirms in law that carbon dioxide, which their products produce, are dangerous, Whitehouse told the Guardian. It also gives the EPA the authority to regulate those emissions under the Clean Air Act.
The letter, which asks for all relevant private communications between the day Trump was re-elected in November to the day the EPA announced plans to rescind the endangerment finding in July, was sent to oil giants Exxon, Chevron, Shell, and BP, as well as coal producers, a rail giant and two auto manufacturers, whose business plans rely on fossil fuels.
“The only interests that benefit from undoing the endangerment finding are polluter interests, and specifically fossil fuel polluter interests,” Whitehouse said.
It was also sent to trade associations and law firms representing big oil and auto companies. And it was sent to far-right, pro-fossil fuel thinktanks Competitive Enterprise Institute, New Civil Liberties Alliance, the Heartland Institute, America First Policy Institute, and the Heritage Foundation, each of which challenge the authority of federal agencies, and some of which have directly praised the proposed endangerment finding rollback.
The Guardian has contacted each recipient for comment.
Because Republicans control the Senate, Democrats on the environment and public works committee lack the power to subpoena the documents. But the Senate committee still expects the companies to comply with their request.
The letter could send a signal to polluting sectors and rightwing firms that they are being watched, and could set the stage for continued investigation if Democrats win back a congressional chamber in next November’s midterm elections.
Fossil fuel interests pushed back on the endangerment finding when it was first written, yet little is known about more recent advocacy to overturn it. Immediately following the EPA’s announcement of the rollback, the New York Times reported that groups have not “been clamoring in recent years for its reversal”. But Whitehouse believes that has changed since Trump was re-elected in November 2025.
When Joe Biden was president and Democrats controlled at least one chamber of Congress, Whitehouse said “a request to rescind the endangerment finding would have just looked like useless, pointless, madness.
“But now that they can actually do it in their desperation and with the mask of moderation pulled off, I think it’s very clear that they were directing this happen,” he said.
Under Trump, former lobbyists and lawyers for polluting industries such as oil, gas and petrochemicals have entered leadership positions at the EPA.
“The fossil fuel industry owns and controls the Trump administration on all matters that relate to their industry, and they have subservient Republicans controlling both the House and the Senate,” said Whitehouse. “The change in power has allowed a change in tactics and attitude.”
Two environmental non-profits have sued the Trump administration for “secretly” convening a group of climate contrarians to bolster its effort to topple the endangerment finding.
The EPA’s proposed undoing of the crucial legal conclusion comes as part of a larger war on the environment by the Trump administration, which has killed dozens of climate rules since re-entering the White House in January.
“The motive is to help fossil fuels survive,” said Whitehouse.
