Standing alongside former Vice President Al Gore and six fellow state attorneys general, New York’s Eric Schneiderman in March announced the formation of a new coalition called AGs United for Clean Power. Its goal, according to Schneiderman, would be to investigate whether fossil fuel companies and industry groups are misleading the public about the dangers of climate change.

Made up of attorneys general from 15 states as well as the District of Columbia and the U.S. Virgin Islands, the coalition says it will also fight to protect the Environmental Protection Agency’s Clean Power Plan. “With gridlock and dysfunction gripping Washington, it is up to the states to lead on the generation-defining issue of climate change,” Schneiderman said. “We stand ready to defend the next president’s climate change agenda, and vow to fight any efforts to roll back the meaningful progress we’ve made over the past eight years.”

This kind of activism on the part of attorneys general is not new. In many ways, AGs United for Clean Power is just the latest example of how the role has evolved over the past two decades from law enforcer to de facto national policymaker -- an evolution that began in the late 1990s with state and federal lawsuits against the tobacco industry. “The tobacco lawsuits were the big bang for AG activism,” says Paul Nolette, a Marquette University political scientist and author of a book on AGs and their evolving role called Federalism on Trial.

In fact, AGs United for Clean Power likens its mission to that of the tobacco lawsuits, which resulted in massive and lucrative settlements for the states. And indeed, the two share a lot in common. Just as the states found that the tobacco industry knew its product was addictive and caused lung cancer -- but was negligent in telling smokers about those risks -- AGs hope to expose that the oil and gas industry knew of the climate risks associated with carbon dioxide emissions but funded research to cover them up.

So, as with the tobacco lawsuits, these state AGs are taking a more aggressive tack and going directly after companies. A month after the formation of the coalition, Massachusetts AG Maura Healey issued a subpoena requiring ExxonMobil to hand over 40 years of internal communications relating to whether the company misrepresented its knowledge of climate change to investors. New York had issued a similar subpoena to the oil and gas giant in November 2015. Exxon is cooperating with that subpoena because New York state law gives its AG the nation’s broadest authority to investigate financial and shareholder fraud. But the company isn’t cooperating with Massachusetts’ subpoena -- it’s fighting that in federal court.

The similarities to the tobacco lawsuits end there. The biggest difference is party politics: AGs United for Clean Power is made up exclusively of Democratic officials. “All 50 states were involved in the tobacco settlement in 1998,” says Nolette. “This coalition just helps to show how AGs have become entrenched in the partisan, ideological landscape.”

It’s true that both Democratic and Republican attorneys general have become more active on policy issues in recent years. But in the case of AGs United for Clean Power, the coalition is not only all Democratic but has also aligned itself with environmental groups. New York’s Schneiderman announced the group’s formation next to Gore, who is now chairman of the Climate Reality Project. “It’s not like they’re hiding anything here,” says Nolette. “But it raises questions: Are AGs becoming like an interest group? Is that what AGs have become in at least this slice of litigation?”