State attorneys general have long used their power to shape federal policy, and their involvement in a case can have a significant impact, often giving litigants legal standing to challenge the government. 

“From a legal perspective, it’s really helpful for a state to be on the case,” said Mark Templeton, head of the environmental law clinic at the University of Chicago’s law school, and a former environmental regulator in Missouri. 

“There are specific and useful state interests in these national policies.”

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