The Union of Concerned Scientists (UCS) this week filed to sue the Environmental Protection Agency in federal court.
The lawsuit is over an EPA policy that changes who can serve on its advisory boards.
Last October, EPA administrator Scott Pruitt banned current EPA grant recipients from serving on the agency's 23 advisory boards, describing the move as a way to preserve "independence."
But the UCS argues that the policy undercuts independent oversight while favoring industry insiders over academic scientists.
Thomas Sisk, an ecologist at Northern Arizona University and current UCS member, said committee nominees already undergo rigorous vetting for conflicts of interest.
"I think what may be lost in this whole debate is the fact the scientists who receive funding to conduct research are the most qualified people to advise on those topics," Sisk said.
The lawsuit asks the court to declare the policy arbitrary and illegal, and to issue an injunction barring its execution.