U.S. Senators, led by Sheldon Whitehouse (D-RI), Ranking Member of the Senate Environment and Public Works Committee, have begun an investigation into Environmental Protection Agency (EPA) Administrator Lee Zeldin’s decision to repeal the 2009 endangerment finding. This scientific determination is central to the EPA’s authority to regulate greenhouse gas emissions.
The senators argue that the process for repealing the endangerment finding lacked transparency and public engagement. In their letter to Administrator Zeldin, they wrote, “Presidential policy preferences do not give EPA carte blanche to bypass statutory mandates to engage in good faith with sound science and public input in favor of predetermined outcomes.”
The 2009 endangerment finding was based on peer-reviewed science following the Supreme Court’s Massachusetts v. EPA decision. It provided a legal basis for U.S. climate policy and has been upheld twice by the D.C. Circuit, with the Supreme Court declining further review. The senators contend that repealing this finding disregards decades of scientific evidence and could lead to relaxed pollution standards for vehicles, power plants, airplanes, and other sources.
In their communication with Zeldin, the senators highlighted his previous statements: “you have described the endangerment finding as the ‘holy grail of climate change religion,’ and stated that under your leadership, EPA would be ‘driving a dagger through the heart’ of climate regulation. In media appearances and official communications, you framed repeal as ‘the largest deregulatory action in the history of the United States,’ emphasizing cost savings and ideological opposition rather than engagement with the statutory endangerment standard—or with the massive costs to human health and welfare that greenhouse gas-driven climate change imposes.”
Internal documents indicate that plans for repeal were underway before regulatory reviews were complete or public comments considered. The senators cited reporting that “internal agency notes and presentation slides show that you ‘intend[ed] to sign off . . . on the final policy and legal justifications for repealing the so-called endangerment finding and . . . climate rules for cars and trucks…’”
Administrator Zeldin reportedly intended to justify repeal using a Department of Energy report from a working group criticized for lack of transparency and balance. A federal judge found this group violated requirements under federal law: “federal judge … ruled that the DOE violated federal law when Secretary Wright hand-picked the five researchers and convened the Working Group in secret, finding that its formation and operation breached the Federal Advisory Committee Act’s requirements for transparency, public meetings, and balanced viewpoints... The collapse of the Working Group effort simply underscores that EPA attempted, and failed, to manufacture support for a conclusion the established scientific record does not and cannot sustain.”
The senators added: “When an agency signals that the outcome of a proceeding is preordained, public participation becomes performative rather than meaningful, undermining legitimacy of rulemaking process… Presidential policy preferences do not give EPA carte blanche to bypass statutory mandates to engage in good faith with sound science and public input in favor of predetermined outcomes.”
The letter was signed by 41 Democratic senators including Chuck Schumer (D-NY) as well as independents Angus King (I-ME) and Bernie Sanders (I-VT). They requested documentation about EPA’s legal reasoning by February 27, 2026.
Previously, Senate Democrats called on President Trump’s administration to withdraw its proposed rollback: they described it as a “dereliction of duty” and a “blatant failure to protect American people.” Whitehouse had also criticized EPA’s proposal as “political rhetoric masquerading as legal and scientific reasoning” serving only fossil fuel industry interests while ignoring scientific consensus about climate risks.
None of these concerns were addressed in EPA's final ruling.
The Senate Environment and Public Works Committee operates from its administrative base in Washington's Dirksen Office Building according to its official website. The committee oversees federal programs related to environmental quality, natural resources management, infrastructure legislation affecting national environmental policy across all states (source). It collaborates through subcommittees focused on clean air issues among others (source).
