Vermont made history last year when it enacted the country’s first climate superfund law. It’s designed to let the state recover money from fossil fuel companies to help pay the rising costs of climate change.

If the law can survive intensifying legal challenges, that is.

On Thursday, the Justice Department filed federal lawsuits against Vermont and New York, the only other state to have enacted a climate superfund law, arguing that the measures were “a brazen attempt to grab power from the federal government” and force others to pay for the states’ infrastructure spending.

Hours later, West Virginia’s attorney general, John B. McCuskey, announced that he was leading another challenge to Vermont’s law, saying the measure would “fine America’s coal, oil and natural gas suppliers into oblivion.”

Mr. McCuskey had already filed a similar lawsuit against New York’s law, which seeks $75 billion from oil and gas companies over the next 25 years. On Thursday, he said Vermont’s version might be “even more dangerous” because it has no monetary cap.

He and 23 other attorneys general are seeking to join a lawsuit filed late last year by the U.S. Chamber of Commerce and the American Petroleum Institute, an industry group, in federal court in Vermont.

West Virginia is a major producer of natural gas and coal. Its complaint argues that the activities of fossil-fuel companies are legal and that “Vermont seeks to have its cake and eat it too, by both reaping the benefits of affordable and reliable fuel, yet penalizing the entities that help produce such fuel.”

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