Republicans want the EPA to show its work, but critics see a backdoor assault on climate rules.

There’s nothing Lamar Smith would like more than to get rid of President Obama’s climate-change agenda, which he has said contains “some of the most expensive and burdensome regulations” in the history of the Environmental Protection Agency and is based on “science-fiction promoted by alarmists.”

The Republican-led House has offered no shortage of opportunities for that—proposed spending bills have slashed funding for the climate plan, and there have been measures to freeze EPA rules, to emphasize their economic cost, and to expand drilling even while the administration tries to shift to renewable energy.

The jurisdiction of the Science Committee doesn’t afford Smith as chairman the opportunity to advance legislation freezing regulations or cutting off funding to the EPA. But he has carved out a role that he thinks could stop the climate agenda right at its roots—the scientific justification.

Smith has repeatedly dismissed the scientific consensus that climate change is real and is happening as a result of human causes. He’s also fond of questioning the impact that the administration’s climate-change agenda might have—in an exchange with EPA Administrator Gina McCarthy, he said regulations on power plants would only avert sea-level rise by the thickness of three sheets of paper. (The EPA, meanwhile, says that the standards will have a much greater effect in conjunction with other efforts.)

He has also gone directly at the scientific support for agency rules, part of an attack on what he calls “secret science.” He says that the administration has been keeping under wraps the data and analysis that backs up its environmental regulations and thus may be overstating the benefits of its rules.

“They're basically saying: 'Trust us. We'll use the data that we want to. You can't see it, but we think it justifies each regulation,’” Smith said in an interview.

“Give us the data, and we want it to be peer-reviewed, we want other scientists to evaluate it, we want the American people to see it,” he said. “And the fact that they're not doing it makes me very suspicious that the data does not show what they claim.”

This spring, the House passed Smith’s “Secret Science Reform Act,” which would require all EPA regulations to be based on publicly available data or studies that can be replicated. A Senate committee has approved a companion bill, although it has not made it to the floor, and the White House has promised a veto should it reach the president’s desk.

It’s part of a suite of bills that go after the scientific backing for the administration’s regulatory agenda. The Science Committee has also moved a bill reforming the makeup and role of the Scientific Advisory Boards that EPA relies on to back up its regulations. And a separate bill from the Judiciary Committee that passed the House would crack down on and tighten requirements for cost-benefit analyses and open up more public-comment opportunities.

Supporters say the goals are justifiable: Regulations should be based on public data, and independent scientists should be able to form their own analyses. Even President Obama called for more scientific transparency early in his first term. As Rep. Jim Bridenstine, an Oklahoma Republican, once asked at a hearing on the secret-science bill: “Is it too much to ask the EPA to follow the same guidelines I give my children in elementary school? Show your work?”

But Democrats and scientific organizations say those intentions aren’t so noble.

“I’m all in favor of data, where appropriate, being made publicly available. But this isn’t about that,” said Andrew Rosenberg, director of the Center for Science and Democracy at the Union of Concerned Scientists. “This is about telling the EPA they can’t move forward on their regulations and precluding them from using a number of studies on public health.”

The EPA has said that it’s simply impossible to turn over some of the data the Science Committee wants without disclosing confidential personal information. Attempts to get raw data from universities and other institutions, then strip it of any information that could identify individual patients, has proved time-consuming and costly.

A Congressional Budget Office report said that under Smith’s bill, EPA could end up paying between $10,000 and $30,000 for each study and, absent a funding increase, the measure would likely halve the number of studies EPA can rely on.

A March letter from various universities and science groups—including the American Association for the Advancement of Science and the American Geophysical Union—warned that the bill was too vague. For example, the groups said, many public-health studies would not be able to be replicated because they are “longitudinal studies that are so large and of great duration that they could not realistically be reproduced.”

The end result, said Joanne Carney of AAAS, is that the scientific process would become subject to judicial review, and you’d have “courts determining these standards, rather than the scientific community.”

The transparency approach is also finding its way to other environmental rules. For example, in recent Congresses, there have been various bills requiring Endangered Species Act listings to be backed up by public science. And Republicans have increasingly questioned the EPA’s cost-benefit analyses for regulations, accusing the agency of relying on bunk calculations that underestimate how expensive their rules will be. Rosenberg said it was part of an agenda to “see the scales tipped even further in favor of special interests.”

To Smith, though, it’s a campaign that he doesn’t plan to stop. His committee has already obtained some data from EPA for a number of studies backing up its clean-air regulations, like limits on ground-level ozone, and he expects it to continue. After all, he says, why wouldn’t the EPA want to comply with his committee’s subpoenas?

The panel is “just trying to get the EPA to be forthright, to be open and honest, and to come clean with the American people,” he said.