Sometimes a bad piece of legislation doesn’t die, it just returns in another form—call it a zombie bill. In this case, the zombie is a bill that morphed into a proposed rule that would upend how the federal government uses science in its decisionmaking. It would allow the US Environmental Protection Agency to pick and choose what science it uses to write legislation on air, water, and toxic pollution that affects human health and the environment.

Republicans tried to pass this type of legislation from 2014 to 2017, with titles such as the Secret Science Reform Act, followed the next year by the Honest and Open New EPA Science Treatment Act. The idea, which on the surface seems like a good one, was to force the EPA to use only research that is publicly accessible, reproducible, and independently verified.

Critics, including much of the US scientific community, complained it would throw out nearly all epidemiological studies in which patients give consent to use their medical information but not their names, to protect their privacy. That would mean limiting studies on the effects of air pollution on lung disease or toxic chemicals’ effects on Parkinson’s disease and cancer, for example. Scientists also argued that some data, by its nature, can never be reproduced. That would include, for example, the collected particles spewed out by erupting volcanoes, or oil-stained creatures from the Deepwater Horizon spill, or tissue samples taken from soldiers exposed to Agent Orange during the Vietnam War.

Despite years of hearings and committee votes, these bills never passed the Senate. The Democrats took over control of the House in 2018, and so current EPA administrator and former coal lobbyist Andrew Wheeler isn’t going to Congress a third time. Instead, the so-called science transparency legislation has been resurrected in the form of an EPA regulation that doesn’t need congressional approval.

The proposal stirred controversy in 2018, when the Union of Concerned Scientists obtained emails revealing that EPA scientists were excluded from giving input on the rule, which would also allow the EPA administrator to exempt any studies from the transparency requirements on a case-by-case basis.

“This is not being driven by scientists at the agency, it’s being driven by political staff who have spent their careers trying to reduce the authority that the EPA has,” says Michael Halpern, deputy director of the Union of Concerned Scientists’ Center for Science and Democracy. Halpern noted the proposal has been championed by chemical and tobacco industry groups that have for years sought to reduce the EPA’s regulatory powers.

The Strengthening Transparency in Regulatory Science rule would require that scientists disclose all of their raw data, including confidential medical records, before the agency could consider an academic study’s conclusions, according to a draft copy obtained this week by The New York Times.

At a hearing of the House Science Committee on Wednesday entitled Strengthening Science or Strengthening Silence?, EPA science adviser Jennifer Orme-Zavaleta was put in the difficult position of defending a regulation she either wasn’t able to discuss or didn’t seem to know about. Although Orme-Zavaleta has spent 38 years at the agency and is its top scientist, she isn’t reviewing the new rule and couldn’t answer many questions from the congressional panel.

Although the rule only applies to future regulations and is not retroactive, Orme-Zavaleta didn’t know if it could be used to overturn existing health standards when they come up for periodic review every few years. She also didn’t know how the EPA administrator would grant exemptions to the requirement that data from studies used to justify EPA rules have to be made public. “That’s currently being discussed and debated,” Orme-Zavaleta said in response to a question from US representative Bill Foster, a Chicago-area Democrat and former nuclear physicist.