A coalition that supports state attorneys general opposing the Trump administration's rollback of environmental regulations says the top lawyers in mostly progressive states have taken at least 80 actions in the past year to challenge those moves.

The State Energy & Environment Impact Center published a report Tuesday documenting the actions of state attorneys general who have used a variety of tactics to challenge the Trump administration as it seeks to delay or repeal a number of Obama-era environmental regulations.

"This report makes clear the outsized role state attorneys general are playing in advancing and defending progressive policies, regulations and values pertaining to environmental protection, the causes and impacts of a changing climate and the development of a clean energy economy," said David J. Hayes, executive director of the State Energy and Environment Impact Center. "State attorneys general are upholding the rule of law and stopping unlawful actions dead in their tracks at the courthouse. Attorneys general have also been active in shaping outcomes in advance by speaking out about the harms potential actions would have on their constituents.”

The coalition launched in August 2017 as a way to organize the actions of state attorneys general who are eager to counter the Trump administration’s aggressive environmental and energy agenda.

Attorneys general who have worked closely with the coalition include California’s Xavier Becerra, Massachusetts’ Maura Healey, Maryland’s Brian Frosh, and New York’s Eric Schneiderman, all Democrats.

The attorneys general have been aggressive in the courts, suing the Trump administration for actions including delaying the Waters of the United States rule, eliminating a rule to limit methane emissions, missing a deadline to implement standards for controlling smog-forming pollution, and suspending a requirement that states track on-road greenhouse gas emissions.

Some of these have already been successful.

In July, a federal appeals court blocked the Trump administration from eliminating an Environmental Protection Agency rule limiting methane emissions from oil and natural gas wells.

Last week, a federal court ruled the Trump administration must enforce a different Obama-era rule intended to cut methane emissions from natural gas drilling on public land.

In a fiery ruling, Judge William Orrick granted a preliminary injunction against the Interior Department’s Bureau of Land Management, stating the Trump administration’s attempt at delaying the methane rule was "untethered to evidence."

Also this month, a federal court ruled the Trump administration must implement Obama-era energy efficiency regulations that it had delayed making official.

The Trump administration has reversed course on plans to roll back environmental regulations at least 10 times in response to a court decision or lawsuit, according to Politico.

In addition to filing high-profile lawsuits, the attorneys general have filed public comments and written letters opposing Trump administration actions before they become official, threatening to take legal action.

For example, in January 2018, a coalition of 12 state attorneys general, led by Becerra, filed comments with the EPA, requesting that it withdraw the proposed repeal of the Obama-era Clean Power Plan.

The comments allege EPA Administrator Scott Pruitt is not an unbiased decision-maker, as required by the Administrative Procedure Act, because he sued the Obama administration for creating the Clean Power Plan when he was attorney general of Oklahoma.

The Clean Power Plan, intended to reduce power plant emissions, was the main U.S. pledge as part of the international Paris climate agreement, which the Trump administration intends to leave. The plan was never implemented because of court challenges.

The group of state attorneys general, led by Becerra, has also threatened to take legal action if the EPA attempts to weaken air pollution standards for passenger cars and light-duty trucks for model years 2022-2025.

The EPA has an April 1 deadline to decide whether the regulations should be revised.