Ann Carlson
Ann Carlson
Cara Horowitz
Cara Horowitz

Ann Carlson is the Shirley Shapiro Professor of Environmental Law in the UCLA School of Law. Cara Horowitz is co-executive director of the Emmett Institute on Climate Change and the Environment at the UCLA School of Law. This op-ed appeared in the Washington Post.

The Environmental Protection Agency’s proposed repeal of stringent vehicle emissions standards is the agency's biggest assault on public health and the environment yet. The proposal would worsen climate change — a problem that many in the Trump administration don’t even acknowledge — and eviscerate the most effective tool Americans have to fight air pollution: California’s special authority to cut tailpipe emissions from cars.

The EPA’s proposal would revoke California’s permission to continue an ambitious clean-cars program that regulates not just greenhouse gases but also the pollutants that create smog and cause asthma, heart and respiratory disease, and cancer. The program also accelerates the adoption of zero-emission vehicles. Thirteen states and the District [of Columbia] have signed on to California’s standards in whole or in part. The administration is proposing to eliminate the heart of the program.

To understand why the EPA’s proposal is so damaging, it’s worth looking at the history of our government’s response to air pollution.

California’s leadership on auto pollution began in the 1940s and 50s when a haze of toxic smog regularly hovered over schools, homes and workplaces. Mountains trapped vehicle emissions in the state’s desert basins. California was the first state to regulate emissions from cars, beginning in the 1960s.

In 1967, Congress prohibited other states from regulating auto pollution but let California continue. There was one hitch: The state’s standards had to be tougher than the federal standards. This arrangement has produced one of the country’s greatest environmental accomplishments: cleaning up polluted air. California has led the United States in setting tough standards, with the federal government usually following the state’s lead a year or two later.

Progress in Los Angeles, long infamous for its smog, shows just how well this arrangement has worked. In 1977, Southern California experienced 121 Stage 1 smog alerts for violating federal ozone standards. The region hasn’t had a Stage 1 smog alert since 2003. Los Angeles used to violate carbon monoxide standards more than 100 times a year. The Southern California basin no longer violates the standard , nor does any other air district in the country.

Tailpipe regulations also led to the widespread use of unleaded gas, nearly eliminating lead in the atmosphere. Our air is much cleaner than it was four decades ago in large part because combined California and federal leadership have made cars 99 percent cleaner.

The work to clean up the country’s air quality, though, is not done. Cars and trucks are still the biggest culprits for ozone and particulate pollution. In California and around the country, many urban areas continue to violate federal ozone standards. Millions of Americans breathe unhealthy air polluted with particulate matter. People who live near highways and heavily trafficked roads — often low-income communities and communities of color — breathe the worst air and suffer the health consequences.

Climate change is making air pollution worse. As average temperatures increase, so does ozone pollution. In the West, more frequent and intense wildfires increase particulate pollution. We need all of the tools at our disposal to keep the country from backsliding on air quality, let alone to improve it.

The EPA’s move to revoke California’s waiver is unprecedented in agency history and legally indefensible. Under the Clean Air Act, the EPA must approve California’s tailpipe regulations as long as California can show that its circumstances are “compelling and extraordinary,” which the agency has done more than 100 times for California. Only one waiver has ever been denied, but the EPA ultimately changed its mind and let California regulate.

There’s no justification for revoking this waiver. Every presidential administration for 50 years has considered California’s air quality problems “compelling and extraordinary.” California’s climate problems are already on display: droughts, fires, sea level rise and the early melting of the Sierra snowpack that supplies much of California’s water. Transportation is the largest source of climate emissions for both California and the country. What could be more compelling than allowing the state to clean up its automotive fleet to eliminate the emissions causing these problems?

President Trump’s EPA has said that one of its core principles in “reforming” environmental regulation is to restore power to the states. This proposal to yank authority from California violates this principle. The administration says that California is imposing its standards on the rest of the country. But this is just wrong: Each state gets to choose for itself whether to follow California or federal standards.

The EPA’s proposal is hypocritical, and the administration’s argument in its favor is incorrect. If the proposal is finalized and, as is inevitable, California sues, even a conservative Supreme Court would likely reject it as indefensible and wrong-headed.