A coalition of 24 U.S. states, alongside 15 cities and regions*, announced that they have filed a lawsuit in federal court, challenging the Trump administration’s repeal of the landmark 2009 Endangerment Finding underlying the U.S. government’s ability to regulate greenhouse gas (GHG) emissions from the automotive sector and underpinning GHG regulations across other carbon-intensive sectors.

The challenge, led by the Attorneys General of California, Connecticut, New York and Massachusetts, argues that the Trump administration’s move ignores overwhelming scientific evidence confirming the impact and danger posed by climate change and the government’s legal obligation to regulate the GHG emissions that contribute to that danger.

California AG Rob Bonta said:

“With the unlawful rescission of the Endangerment Finding, President Trump and his EPA have abandoned their most important mission: protecting the health and welfare of the American people. The science doesn’t lie. Climate change and GHG emissions are harming public health and causing devastating and ever-worsening disasters.”

The suit follows the repeal in February by the U.S. Environmental Protection Agency (EPA) of the Endangerment Finding, reached in 2009 by the Obama-era EPA, that found that GHG emissions endangered public health and welfare through impacts including global warming, by contributing to extreme weather events, heat-related mortality, and by reducing air quality.

The finding underpinned the ability of the EPA to issue a series of regulations aimed at reducing greenhouse gas emissions from sectors, with the agency issuing its first GHG standard for light-duty vehicles in 2010, followed by standards for medium and heavy-duty vehicles in 2011. The Agency has also issued GHG standards for sectors such as power generation and the oil and gas sector which could be impacted by the new move.

Alongside the repeal of the finding, the EPA said that it would no longer have the statutory authority to prescribe standards for GHG emissions, and that it would remove all GHG standards for light-, medium- and heavy-duty vehicles and heavy-duty engines.

The new lawsuit argues that the recission of the finding conflicts with a 2007 Supreme Court decision that GHG emissions qualify as pollutants under the Clean Air Act, and that the repeal violates the Act, which obligates the EPA to regulate pollutants found to endanger public health and welfare.

The suit asks the court to vacate the Trump administration’s recission, which would reinstate the Endangerment Finding.

New York AG Letitia James said:

“Across our country, communities are already suffering from climate disasters. From freak storms to devastating floods to deadly cold snaps and unbearable heat waves, the climate crisis is here, and it is already reshaping the way we live. Instead of helping Americans face our new reality, the Trump administration has chosen denial, repealing critical protections that are foundational to the federal government’s response to climate change.”

President Trump, who recently referred to climate change as “the greatest con job ever perpetrated on the world,” has worked actively in his second term to undo the climate-focused actions of prior administrations, starting with an Executive Order on his first day in office to once again withdraw from the Paris Agreement, in addition cancelling billions in federal clean energy awards, and attempting to halt activity on all major U.S. offshore wind projects. Most recently, this month the administration filed a lawsuit in federal court aimed at striking down California regulations requiring automakers to reduce fleetwide vehicle CO2 emissions and increase the proportion of zero emission vehicle (ZEV) sales.

*In addition to California, Connecticut, New York and Massachusetts, the lawsuit was joined by the Attorneys General of Arizona, Colorado, Delaware, Hawai‘i, Illinois, Maine, Maryland, Michigan, Minnesota, New Jersey, New Mexico, Nevada, North Carolina, Oregon, Rhode Island, Vermont, Virginia, Washington, Wisconsin, the District of Columbia, as well as by Pennsylvania Governor Josh Shapiro, the cities of Albuquerque, Boston, Chicago, Cleveland, Columbus, Denver, Los Angeles, New York, San Francisco, Santa Clara, Harris County, Texas, Martin Luther King Jr. County, Washington and the U.S. Virgin Islands.