The Environmental Protection Agency has banned scientists who receive funding from the agency from serving on its scientific advisory boards, in an unprecedented move that critics say gives favor to industry-friendly advisers.

At a Tuesday afternoon event rolling out the new policy, Administrator Scott Pruitt invoked a biblical tale from the book of Joshua, in which the pagans are instructed to choose this day whom you will serve, either God or the gods of your fathers.

As it relates to grants from this agency, youre going to have to choose, said Pruitt, who described the new rule as a way of ensuring theres integrity in the process and that the scientists that are advising us are doing so without any kind of appearance of conflict.

Pruitt described scientists who received as much as $77 million in grants from the agency while also serving on advisory boards as damaging the perception of independent rule-making. Pruitt signed an order cementing the new rules into policy during the 28-minute event, with Sen. Jim Inhofe (R-Okla.) and Rep. Lamar Smith (R-Texas), two of the most ardent climate change deniers in Congress, at his side.

Democratic lawmakers denounced the announcement as unprecedented.

Administrator Pruitt is purging expert scientists from his science boards and replacing them with mouthpieces for big polluters, Sen. Tom Udall (D-N.M.) said in a statement. Now, instead of independent science guiding the way, hired guns for industry will be steering EPA policy on central issues affecting clean air, clean water, and public health.