24 Governors Call on Trump to Halt Rollback on Rules for Clean Cars

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The opposition to one of President Trump’s most consequential regulatory rollbacks — a plan to weaken pollution standards for automobiles nationwide — widened on Tuesday when 24 governors, including three Republicans, urged the president to abandon his plan.

The governors’ plea adds to a chorus of criticism from an unlikely mix of voices, including not only environmentalists and labor unions but also some of the biggest automakers in the world. The two dozen governors include the leaders of four states — North Carolina, Pennsylvania, Wisconsin and Montana — that voted for Trump in 2016, helping propel him into the White House.

“Strong vehicle standards protect our communities from unnecessary air pollution and fuel costs,” the group wrote. The statement also noted that vehicles are “the largest source of carbon pollution in the United States,” a reference to the need to fight climate change by sharply reducing the amount of carbon dioxide pumped into the atmosphere.

The Trump administration’s rule changes, which are expected to land later this year, would weaken Obama-era rules that would have doubled the fuel economy requirement for new passenger vehicles by 2025 as part of Mr. Obama’s signature effort to fight global warming. President Trump has questioned the scientific consensus of climate change and has suggested that it is a hoax.

A White House spokesman, Judd Deere, said that the Trump administration “believes strongly in a national fuel standard that promotes safer, cleaner, and more affordable vehicles,” adding that “the federal government, not a single state, should set this standard.”

Outspoken opposition is growing to the new rules, notably from some influential manufacturing industries that Mr. Trump has pledged to help.

Last month, 17 automakers asked Mr. Trump to soften his approach, saying his plan threatened to hurt their profits and produce “untenable” instability in the auto market given that California, a handful of other states and Canada are already expected to keep enforcing the stricter, Obama-era standards. That raises the specter of a national auto market split in two, and a messy legal battle.

The governors also called on Mr. Trump to honor California’s legal right to write its own clean-air rules, something the administration has said it is set to challenge, according to a statement by the governors. “We must unite to ensure a strong, science-based national standard, in California and across the country, that increases year over year,” the governors said.

Electric utilities and the chemical industry have also objected to the rule change.

Utilities stand to benefit from stricter emissions rules if it means people buy more electric cars, and the industry is starting to invest in vehicle-charging infrastructure, according to Edison Electric Institute, which represents investor-owned electric companies. Chemical makers, for their part, stand to gain if vehicles must be made ever lighter, potentially including more plastic parts.

The chemical giant Chemours, which has worked with automakers to develop new refrigerants for air-conditioning systems that emit fewer Earth-warming compounds, has said weakening emissions standards would strand investments and “reverse nearly a decade of progress.”

The chemical industry, which has invested in lightweight plastic and polymer composite materials to make cars lighter and more fuel-efficient, has also pushed back against a key argument made by the Trump administration in support of the rollback: that lighter vehicles are less safe.

Those studies “are based on outdated technologies and practices,” the American Chemistry Council, an industry group said in an email. “Developing technology to lightweight vehicles spurs advanced innovations and creates high-skilled manufacturing jobs.”

In addition, auto parts suppliers say they have invested in technology that will suffer if emissions standards are relaxed. These parts makers, including start-ups, are often where fuel-saving technologies are developed.

“It’s absolutely unprecedented that the automakers would come out and say ‘please regulate us,’” said John S. Major Jr., regional vice president for the Midwest operations for Achates Power, a small company that develops fuel-efficient engine technology. The pollution standards, he said, “mean jobs, they mean technology leadership, they mean economic gains.”

Last year a group of 10 Michigan cities, many of them home to automotive plants, weighed in to say that the rollback “will put Michigan manufacturing at risk.”

Labor groups say the standards support nearly 300,000 jobs in developing and building fuel-efficient technology for cars. “What happens if the U.S. ceases to be the place where companies choose to invest in the next generation of technology?” said Zoe Lipman of the BlueGreen Alliance, a coalition of the country’s largest labor unions and environmental groups. “It would put these jobs at risk.”

The governors’ demands add pressure on the Trump administration to reconsider. According to the statement, its 24 signatories represent 52 percent of the United States population and include three Republican governors (Larry Hogan of Maryland, Charlie Baker of Massachusetts and Phil Scott of Vermont) as well as governors from four states that voted for Mr. Trump in 2016.

The coalition goes beyond the 16 states and the District of Columbia that have joined California to sue the Trump administration over his clean-car rollback. It also includes states that have not formally signed on to follow clean-air rules set by California, which has the legal authority to write its own rules.

There are some indications that other states are moving toward California and its pledge to retain the stricter rules. Last year, Colorado opted to use California’s vehicle emissions standards, and California has said it is in talks with other states as well.

Melissa Baldauff, a spokeswoman for Wisconsin’s governor, Tony Evers, said that while he supported states’ rights to adopt more stringent standards than Washington, Wisconsin had not yet made a commitment to follow any specific standard.

The widening opposition to the Trump administration’s policies on auto emissions creates an awkward moment for Mr. Trump, who has also announced plans to withdraw the United States from the Paris climate accord, an agreement among nations around the world to fight global warming, and has sought to weaken more than 80 environmental regulations but nevertheless talked up what he described as his environmental leadership in a speech on Monday.

Assuming the Trump administration’s rollback of the auto emissions rules is finalized and survives legal challenges, America’s cars and trucks would emit as much as an extra 321 million to 931 million metric tons of carbon dioxide into the atmosphere by 2035, according to an analysis by the research firm Rhodium Group.

Mary Nichols, chairwoman of the California Air Resources Board, the state’s clean air regulator, said California was winning the battle to retain the stricter regulations.

“We have the largest group of states ever coming together to back our position,” she said in an interview. “The fact that we now have over half the U.S. auto market supporting us indicates that we are going to stick with the standards. The auto industry will not build two sets of cars.”

Ms. Nichols rejected the possibility of compromising on the requirement that automakers put vehicles averaging roughly 36 miles per gallon on the road by 2025, a pace some automakers had called unattainable. However, she said, California was open to negotiating on ways to make it easier for automakers to meet those targets, including the use of more credits to reward fuel-saving technologies.

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