How much can Scott Pruitt really change the EPA?

President-elect Donald Trump' nomination of Scott Pruitt as head of the Environmental Protection Agency immediately sparked sharp criticism from liberals and environmentalists, who fear that the climate-change skeptic will reverse the US course on climate action.

While many critics are concerned about the future of the EPA under the nominee, Pruitt is not as vocally radical on the subject of climate change denial as some of the other names rumored for the position. Of Mr. Trump's cabinet picks, Pruitt also represents a more established Republican voice coming from outside the president-elect's inner circle, which may signal a more traditional, if still antagonistic, Republican path for the EPA over the next four years.

Pruitt's position on climate change makes him the latest of Trump's cabinet picks, along with Ben Carson, future head of the Housing and Urban Development, and Betsy DeVos, future education secretary, to have philosophical objections to the level of government regulatory power held by the agencies they will be in control of next year. Their positions on these issues are clear, but their ability to fundamentally alter the role of their agencies may be overestimated, observers say.

Pruitt has used his position as attorney general in Oklahoma, a state which relies heavily on oil and natural gas production, to sue the EPA over regulations designed to curb production of methane, a potent greenhouse gas, from the oil and gas sector. He also was involved in a coalition of state attorneys that sued to block the Clean Power Plan, President Obama's signature environmental policy aimed at reducing emissions associated with electricity production.

"It's a safe assumption that Pruitt could be the most hostile E.P.A. administrator toward clean air and safe drinking water in history," Ken Cook, head of the Environmental Working Group, a Washington research and advocacy organization, told The New York Times.

But while Pruitt's appointment by the president-elect is indicative of Trump's desire to eliminate Mr. Obama's climate change legacy, his actual power as EPA administrator will be limited.

"The EPA administrator has substantial policy discretion in choosing how to implement federal environmental statutes, but this discretion is constrained by the substantive requirements of existing environmental laws as well as by the procedural requirements for agency actions," Jonathan H. Adler, a law professor at the Case Western Reserve University School of Law in Cleveland, tells The Christian Science Monitor in an email. "How much discretion the administrator has depends on the specific issue or policy in question. So, for example, Administrator Pruitt would have the ability to unwind the Clean Power Plan by rescinding the relevant EPA regulations through a new rulemaking, but it is unlikely that he would be able to undo or reverse the 'endangerment finding' that is the basis for many other EPA actions on climate change."

Many of Trump's picks for positions on his cabinet so far have been political outsiders and businesspeople within the president-elect's own inner circle. Pruitt is relatively unconnected to the Trump campaign, and his nomination is likely a result of requests by his transition team that Trump's picks should include more state officials and people not already connected to the president-elect, according to The Wall Street Journal. Still, Pruitt's views on the environment and pro-business policies for oil and gas seem to align pretty well with Trump's.

Trump has called climate change a "hoax," while Pruitt maintains that the "debate" on climate change is ongoing, despite a near-total consensus in the scientific community that human-caused climate change is a real phenomenon. But Dr. Adler says that there may be a silver lining in choosing Pruitt for many environmentalists, at least compared to other, more vocal climate change deniers that could have been appointed.

"I expect environmentalists will find Pruitt to be more pragmatic as an administrator than they expect," says Adler. "As state AG, he was regularly on offense, filing aggressive litigation against the federal government. As the administrator of an agency, he will have a very different role and I expect that will influence the course he takes."

By naming a more traditional and pragmatic Republican to the EPA, the agency might not pursue the kind of aggressive environmental reforms as it did during the Obama administration, but it likely will not be dismantled either.

"It's worth remembering that the EPA was created by Richard Nixon (through executive order) and that the greatest legislative expansion of EPA authority came under President George H.W. Bush," says Adler. "Bush's EPA head, William Reilly, also oversaw a dramatic expansion of asserted federal regulatory authority over wetlands, including on private land. Under George W. Bush, the EPA was a mixed bag. It was aggressively pro-regulatory in some areas, but less so in others."

"How successful the new administration is at changing existing policy will depend quite a bit on the team they put together," he adds.