The so-called war on science isn’t quite as broad as that phrase implies. It’s really a war on one particular scientific fact: that fossil fuels are a threat to public health.

Countless Republicans have waged this war over the last decade, but its battle strategy was the brainchild of one man: Lamar Smith. Like many of his peers in the GOP, the Texas congressman has long distrusted the scientific evidence that humans are causing climate change. And ever since he became chairman of the House Science Committee in 2013, he’s used his position to try to undermine that science, as well as the science behind air pollution—namely by pushing two bills that would radically change how the Environmental Protection Agency is allowed to use science and receive scientific advice to craft regulations.

Though routinely passed by the Republican-controlled House in recent years, these bills have proven too extreme for passage the Senate, at least thus far. And yet, when Smith retires next year after 31 years in Congress, he will do so knowing that his goals have been achieved—even if the bills themselves never become law. Those goals were not merely to undermine climate and air pollution science in the public eye, but to ensure that science cannot influence public policy. Barely more than a year into the Trump administration, Smith and the Republicans have won the war on science.

The most consequential sign of Smith’s victory came last month, when EPA Administrator Scott Pruitt sat down with a reporter for the conservative Daily Caller News Foundation* to announce significant changes to the way the agency uses science. No longer would the EPA use scientific research that includes confidential data to develop rules intended to protect human health and the environment. “We need to make sure their data and methodology are published as part of the record,” Pruitt said. “Otherwise, it’s not transparent. It’s not objectively measured, and that’s important.”

This new policy is a near carbon-copy of Smith’s Honest and Open New EPA Science Treatment Act, or HONEST Act, and might seem reasonable on its face. (Who doesn’t want more government transparency?) But the policy, which is opposed by most scientists and non-profit scientific societies, will force the EPA to ignore most of the research showing air pollution can cause premature deaths (including a landmark MIT study in 2013 that found air pollution causes about 200,000 early deaths each year). That’s because the bulk of the peer-reviewed literature on effects of fine particulate matter and other pollutants is based on confidential data: human medical records, which are protected by federal law. Though hundreds of scientists have approved these studies through extensive peer review, Pruitt says the results aren’t reliable because some of the information isn’t publicly verifiable.