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California takes lead in suing Trump over emissions standards authority

Two dozen attorneys general sign on to preserve state’s tough pollution rules

California and a host of other states sued to keep the state's waiver to set its own emission standards. (Photo

California moved as expected Friday, Sept. 20, to sue the Trump administration over stripping its waiver to set tougher emissions standards for passenger cars and light-duty trucks than the federal government.

The issue does not immediately impact heavy-duty trucks, which are regulated separately, according to the California Air Resources Board.

A total of 24 attorneys general and the cities of Los Angeles and New York sued the National Highway Traffic Safety Administration (NHTSA) challenging the preemption of California’s greenhouse gas emissions (GHG) and Zero-Emission Vehicle (ZEV) standards.

On Thursday, Sept. 19, NHTSA and the U.S. Environmental Protection Agency (EPA) issued the “One National Program Rule” enabling the federal government to create a nationwide standard for fuel economy and greenhouse gas emissions. 


“No state has the authority to opt out of the nation’s rules, and no state has the right to impose its policies on the rest of the country,” Secretary of Transportation Elaine Chao said. 

Waiver challenge

The California lawsuit challenges the overturning of the EPA waiver authorized in 2013. The District of Columbia and 13 other states follow California’s emission standards. The coalition contends the Preemption Rule is unlawful and should be vacated.

“Two courts have already upheld California’s emissions standards, rejecting the argument the Trump Administration resurrects to justify its misguided Preemption Rule,” California Attorney General Anthony Becerra said in a statement. “Yet, the Administration insists on attacking the authority of California and other states to tackle air pollution and protect public health.” 


California, whose economy is the fifth largest in the world, has areas such as the South Coast and San Joaquin Valley where car and truck pollution is the largest contributor to air pollution and smog.

California can still enforce its Low Emission Vehicle program and other clean air standards to address harmful smog-forming vehicle emissions, the EPA said.

100 waivers

Under the 1970 federal Clean Air Act, California may apply for a waiver from EPA to set its own vehicle emissions standards that are at least as protective as the federal government’s standards. Over the past 50 years, the EPA has granted 100 waivers to California. 

In January 2012, California adopted its Advanced Clean Cars Program for cars and light-duty trucks in model-years 2017 through 2025. The program combines the control of smog-causing pollutants and greenhouse gas emissions into a single coordinated package.

The state estimates carbon dioxide emissions would be reduced by approximately 14.4 million metric tons a year by 2025 and 25.2 million metric tons a year by 2030. Adding savings from states following California’s guidelines, the emission reductions would nearly triple.

Attorney generals of Colorado, Connecticut, Delaware, Hawaii, Illinois, Maine, Massachusetts, Maryland, Michigan, Minnesota, Nevada, New Jersey, New Mexico, New York, North Carolina, Oregon, Pennsylvania, Rhode Island, Vermont, Virginia, Washington, Wisconsin, and the District of Columbia; as well as the cities of Los Angeles and New York, joined the lawsuit.

The suit claims NHTSA is overstepping its congressional authority by using the Preemption Rule to strike down California’s greenhouse gas and zero-emission vehicle standards under the Energy Policy and Conservation Act (EPCA).  Under the Act, the Trump administration claims only the federal government may set fuel economy standards. That includes state laws, such as tailpipe GHG emissions and ZEV mandates, that impact fuel economy standards.


Alan Adler

Alan Adler is an award-winning journalist who worked for The Associated Press and the Detroit Free Press. He also spent two decades in domestic and international media relations and executive communications with General Motors.