As he continues choosing personnel to fill positions in his new cabinet, the US president-elect, Donald Trump, has turned to another polarizing figure, Scott Pruitt, to head the Environmental Protection Agency (EPA).  One of Trump’s top legal advisers, the Republican is attorney general of the oil and gas state of Oklahoma.  The EPA choice, Washington pundits said – like at least two other of  Trump’s other cabinet picks – signals a roll-back not only of Obama’s environment and climate policies but potentially those of other presidents since the EPA was founded in 1970 under President Richard Nixon.

According to reports, the Oklahoman, who allegedly has received more than $300,000 in contributions from the fossil fuels industry since 2002, has been the driving force behind the legal challenges launched by Republican-led states against President Barack Obama’s environmental and climate legislation aimed at reducing smog and curbing toxic emissions.

During the election campaign, the president-elect dismissed the concept of manmade global warming as a hoax and called Obama’s Clean Power Plan as a “war on coal.” He also pledged to withdraw the US signature from the recent Paris climate accord. While appearing to soften his stance during a meeting with the newspaper New York Times, the nomination of Pruitt and remarks by both men in a news release announcing it appear to indicate that he will indeed take a hard line.

The press statement from the Trump transition team. reported identically by US news media, quotes the president-elect as saying the EPA “has spent taxpayer dollars on an out-of-control anti-energy agenda,” and that Pruitt “will reverse this trend and restore the EPA’s essential mission of keeping our air and our water clean and safe.” The EPA nominee is also on record as having fought to reduce federal government regulation of water quality in US rivers.

In the statement, Pruitt said: The American people are tired of seeing billions of dollars drained from our economy due to unnecessary EPA regulations, and I intend to run this agency in a way that fosters both responsible protection of the environment and freedom for American businesses.” The future EPA chief – provided his appointment is confirmed by the US Senate – in the past has suggested that environmental regulation should be left to the states.

However, commentators have noted that regulation at state level could create a patchwork quilt of differing rules and regulations across the country, making it difficult for states with clean air or water legislation to maintain their standards against neighboring states. Moreover, companies – apart from those engaged in fracking – could have problems deciding where to invest and which production technology to use, as greenhouse gas emissions and toxic waste discharges do not stop at the state line.

New York’s state attorney general, Eric Schneiderman, said he would use “the full power” of his office to wage a legal battle compelling the Trump administration to uphold enforcement of environmental legislation, while Massachusetts senator, Edward J. Markey, said, “Scott Pruitt would have EPA stand for Every Polluters Ally.” Both men are Democrats.

Environmentalists have sharply criticized the latest Trump cabinet nomination, calling the choice deeply troubling.  “Scott Pruitt has built his political career by trying to undermine EPA’s mission of environmental protection,” Fred Krupp, president of the Environmental Defense Fund, said in a statement. Ken Cook, head of the research and advocacy think-tank Environment Working Group, said it is “a safe assumption” that Pruitt could be the most hostile EPA administrator toward clean air and safe drinking water in the agency’s history.