Environmental Protection Agency Administrator Scott Pruitt proposed a new rule Tuesday to overhaul the way science is used to write regulations at the agency, disqualifying huge amounts of peer-reviewed public health research and giving favor to industry-funded studies.

The new rule, widely condemned by scientists and environmental groups as an attack on science, comes nearly two weeks after the White House quietly revamped clean air rules by executive order. Pruitt made the announcement at a 2 p.m. event live-streamed from the EPA, flanked by Rep. Lamar Smith (R-Texas) and Sen. Mike Rounds (R-S.D.), who both introduced but failed to pass bills on which the proposed regulation is based.

In a twist for an event billed as a step forward in transparency, Pruitt took no questions, and the EPA did not invite reporters from major news outlets to attend. The agency did not immediately release a copy of the proposal or respond to questions about when it would become public, issuing only a press release containing seven soundbites praising the rule. Roughly an hour and a half after the event, the EPA sent HuffPost a 27-page PDF of the proposal.

Today is a red-letter day, Pruitt said, decrying the EPAs reliance on traditionally peer-reviewed studies as wrongheaded. He added, Its a banner day.

The rule, first reported by The Washington Post and confirmed by HuffPost Tuesday morning, would deliver a change long sought by conservatives who say secret science unfairly cripples industry. But critics of the new EPA proposal say it blocks the agency from using traditional, peer-reviewed studies that rely on anonymity granted to interview subjects to collect data on their personal health.

It effectively says our premier public health agency will be prohibited from using many or most public health studies, said Andrew Rosenberg, director of the Union of Concerned Scientists Center for Science and Democracy. Its a perfect catch 22.

The proposal aims to do by EPA writ what has been a pet issue for Smith, the controversial head of the House Committee on Science, Space and Technology, for years. Smith has pushed two bills aimed at forcing the EPA to rely solely on research whose raw data could be publicly released, a bow to big industry players, particularly petrochemical companies who complained about research finding higher rates of asthma and other respiratory ailments that resulted from airborne particulates spewing from their plants. The bills passed in the Republican-controlled House, but failed in the Senate.

In general we strongly support the general concepts in the Lamar Smith bill, which is the basis of what Pruitt is doing, said Myron Ebell, director at the libertarian Competitive Enterprise Institute and the former head of Trumps EPA transition team.