Air Date: Week of May 30, 2025

Los Angeles is regularly out of compliance with federal air quality laws. (Photo: Diliff, Wikimedia Commons, CC BY-SA 3.0)

California’s car culture, trucking industry, and weather contribute to chronically bad air that it’s been gradually improving with its own laws and regulations and the blessing of the US Environmental Protection Agency. But now under President Trump, the EPA and Republican Congress are taking away California’s ability to clean up its air. Ann Carlson is a Professor of Environmental Law at UCLA and joins Host Jenni Doering to discuss the legal questions and public health impact.

Transcript

BELTRAN: From PRX and the Jennifer and Ted Stanley Studios at the University of Massachusetts, Boston, this is Living on Earth. I’m Paloma Beltran.

DOERING: And I’m Jenni Doering.

California is way ahead of much of the rest of the US on clean energy and electric vehicle adoption, with over 2 million zero-emission cars on the road. Yet it also has among the worst air quality in the nation. That’s because it’s hard to get around California without a car, and its nearly 40 million residents means there are a lot of vehicles and tailpipes on the road. And a lot of trucks too since nearly 17% of all U.S. imports and exports travel through California at least as of January 2025. Then there’s the weather. Abundant sunshine is a double-edged sword because all that sun and heat turns pollution from tailpipes into ozone, the main ingredient in smog, which settles in the Central Valley and Los Angeles Basin. So, California has a chronic air pollution problem that it’s been gradually improving with its own laws and regulations and the blessing of the US Environmental Protection Agency. But now under President Trump the EPA and Republican members of Congress are taking away California’s ability to clean up its air. Joining us from Los Angeles is Ann Carlson, the Shirley Shapiro Professor of Environmental Law at UCLA. She was also Acting Administrator of the National Highway Traffic Safety Administration under President Biden. Hi Professor Carlson and welcome back to the show!

CARLSON: Thanks. Good to be here.

DOERING: So, we're talking to you, Professor Carlson, because the Republican led Senate has just voted along party lines to overrule the waivers that California receives from the EPA, which allows California to set stricter regulations on clean air under the Clean Air Act. What exactly are those waivers?

CARLSON: So, California has this special authority under the Clean Air Act, which is a federal law, to set its own air pollution standards for mobile sources, that is cars and trucks and other things that move. But it can't do so unless it gets what's called a waiver from the Environmental Protection Agency. The idea of a waiver basically is you're being waived from the preemption that all other states experience, and EPA has to grant that waiver, if California meets certain conditions. It needs to show that it has compelling and extraordinary circumstances, and it also has to show that its standards are at least as protective of public health as any federal standards.

DOERING: And so, I understand that there's three waivers in question here. What do those waivers actually do?

CARLSON: The three waivers cover both cars and trucks. The first one covers something called the Advanced Clean Car two Rule. And it would phase out internal combustion engines and replace them with zero emission vehicles, they could be fueled by things like electricity or hydrogen, by 2035. And then there are two rules that deal with trucks. One is the advanced clean truck rule, and that also requires the penetration of zero emission trucks, although it's not as stringent as the car rule. And then the third is really an odd title. It's called the omnibus NOx rule. NOx are a form of pollution that come out of the tailpipes of vehicles and create ozone, which is the worst smog problem that California faces, and that would cut NOx emissions by about 75% over the next decade.

DOERING: Over a single decade? That sounds like a pretty ambitious timeline.

CARLSON: These are ambitious rules, but that's because California has air districts that don't comply with federal law. They're out of compliance with the ozone standard and with another standard for fine particulate matter. That's really, really tiny particles. And we can't meet those standards currently. For example, Los Angeles doesn't even meet a standard that was set in 1997. There are two standards that have been passed since then that are even more stringent. And so, we are really facing a problem where our air quality continues to violate federal law. I should add, though, that the air quality is much, much cleaner than it used to be. Sometimes, I think we get left with the impression that California, or Los Angeles in particular, is basically a cesspool. The air quality is much, much cleaner. We've cleaned up lead out of the air. We've cleaned up carbon monoxide. Our ozone pollution is at levels that are much, much lower than they used to be, but they still violate federal standards.

DOERING: So, Professor Carlson, I understand that the Senate Republicans were able to use something called the Congressional Review Act to try and revoke these California Clean Air Act waivers. What exactly did they do here?

CARLSON: So, the Congressional Review Act is a very obscure statute that typically allows a Congress that comes in after a presidency changes hands, changes parties, to revoke rules that were enacted in the last days of the administration. Typically, it's in the last 60 days, counted by how many days that Congress is in session. What's weird about the use of the Congressional Review Act here... there's really several things, but the weirdest thing is that waivers are not rules. They are not considered rules by the Government Accountability Office, the Senate Parliamentarian, and yet Congress went ahead and voted to revoke the waivers. Also, the other thing that's weird is that the waivers were actually granted, at least two of them, far earlier than the 60 days required by the statute, but they weren't submitted to Congress — that's one of the requirements of the Congressional Review Act — by the EPA, until January. And that's because under President Biden's Environmental Protection Agency, the waivers weren't considered rules because they're not by the definition of the statute, so they were never submitted. So, EPA then went ahead and submitted them in January, trying to argue that they're rules, despite the fact that legal authorities have said they're not rules. And then the Senate went ahead and voted on them and voted to revoke them anyway. The House did as well.

DOERING: And so, by the way, who is the Senate Parliamentarian and why are they important here?

CARLSON: So, the Senate Parliamentarian really sets the ground rules for the Senate, and it's her decision, typically about what gets voted on and when by the Senate. So, one really good example is a process called budget reconciliation. The Senate can adopt a budget with a majority vote as long as the substance of the budget amendments are about what you're going to spend and what you're going to tax. You can't add on to that budget reconciliation bill a bunch of things that don't have anything to do with the budget. The Parliamentarian will say, "No, that's not subject to the budget reconciliation rules." So, if you stop following the Senate Parliamentarian's basic ground rules, you really blow up the Senate policies and procedures and norms that senators have been governed by and abided by for decades.

DOERING: I think the air quality implications and public health implications of this decision are really important to highlight. So, let's just take a step back and talk about why does California need these waivers more than other states?

CARLSON: So, the Environmental Protection Agency sets standards — they're called the National Ambient Air Quality standards — for pollutants that are kind of everywhere in the air. One of them is ozone pollution. Another, as I mentioned, is fine particulate pollution. They're standards for lead, for carbon monoxide, really nasty pollutants that do terrible things to public health. And they set these standards based on the best science available. And right now, California does not meet the standards, at least in Southern California and in the Central Valley for both ozone pollution and fine particulate matter. And we know that even at quite low levels, ozone pollution causes all kinds of health problems. It causes respiratory problems. It can enhance the possibility of a heart attack. And fine particulate matter is really, really dangerous because it's so tiny, the matter, that it can embed deeply into the lungs, and so it can again interfere with breathing. It can cause cancer. So, this is really a major public health concern. One of the very strange things about revoking the California waivers is that the EPA has been threatening to sanction California for being out of compliance with the standards, and yet, it's taking away the most powerful tool that the state has to address what is the biggest source of pollutants. So, one of the things to watch for is, does EPA try to sanction California? If it does, it revokes its highway funding. So, it's a huge sanction. It's not like a little slap on the wrist. It's basically withholding millions and millions of dollars from the state for failing to meet air pollution laws when it's the federal government itself that's standing in the way of California meeting those standards. There's another real benefit of two of the rules. The Advanced Clean Car Rule and the Advanced Clean Truck Rule would also cut greenhouse gasses and therefore help slow the warming of the planet. That won't happen with the revocation of the waivers.

DOERING: Now, Professor, California Governor Gavin Newsom and Attorney General Rob Bonta have said that they're going to fight this decision in court. What could happen once they do?

CARLSON: Well, one of the strange provisions of the Congressional Review Act, this very obscure statute, is that it says that courts can't review decisions under the Act that are made by Congress. So, California has a tough legal road ahead of it. It may be the case that a court nevertheless is willing to say, "Look, you can't take a statute and apply it to something that the statute itself doesn't cover." So, a court may be willing to rule that in fact, Congress used the Congressional Review Act in a way that it wasn't meant to be used. But there is this provision barring judicial review in the Congressional Review Act, and we're going to have to wait and see what courts do with that provision.

DOERING: So, how could other states besides California be impacted by this decision that the Senate has made?

CARLSON: The Clean Air Act allows all states to make a choice about which vehicle emission standards they follow under a section called Section 177 of the Clean Air Act. The states that follow California's lead, we call the 177 states. And a number of states were going to follow the Advanced Clean Car Two rule. A number of states were also going to follow the two truck rules. It's kind of a different mix of states, depending upon which rule it is. They will not be allowed to do that as long as California does not have a waiver to implement its standards. So that means that something like 40% of the passenger vehicle market was going to be covered by the California standards. It won't be anymore. And a huge part of the truck market also will no longer be covered by the California truck rules, unless they're reinstated by a court.

DOERING: You know, Professor one argument that we've seen the Trump Administration try to make as it goes about undoing clean energy tax credits and trying to roll back some of these policies supporting, for example, electric vehicles from the Biden administration, they've been saying that, you know, we don't want to pick winners and losers. We don't think that we should be giving a leg up to the clean energy industry. What's your response?

CARLSON: Well, first of all, there are a lot of subsidies for fossil fuels, so if you want to level the playing field, then you have to get rid of all sorts of tax breaks and tax incentives that encourage the drilling of oil and so forth. But secondly, we're in a climate emergency, and we need to act. And we need to act with urgency. The Inflation Reduction Act, which contains a lot of the programs that the Trump Administration and now the House Republicans are seeking to roll back, are really the most effective climate bill that has ever passed Congress. So essentially, what you're saying is, okay, we don't care about climate change. We don't care about the fact that the planet is burning, that we are seeing climate events coming at us so rapidly it's hard to keep up with them. It's just unprecedented. And so, to say we're just going to back away from what is, again, the most ambitious climate bill we've ever enacted is really to say we're not going to do anything to try to solve climate change.

DOERING: And Professor Carlson, you know, as a legal scholar, what long term implications of the Senate's decision here worry you the most?

CARLSON: Well, what the Senate did is to effectively blow up the filibuster because if they were really interested in following procedure and scaling back California's authority to regulate under the Clean Air Act, they should do so with the normal bill. And that bill would require a 60-vote majority in the Senate. By using the Congressional Review Act and ignoring the Senate Parliamentarian's decision, they're essentially saying we only think that we're going to try to pass things with 51 votes. That has huge implications far outside of environmental law. That means that anything that normally would be subject to the filibuster could be now voted on with a 51-vote majority. So, I guess the question is, has the Senate opened a Pandora's box that it can't close again? And is it going to result in the busting of the filibuster and the use of the Congressional Review Act for all kinds of actions that it should not be used for?

DOERING: Ann Carlson is the Shirley Shapiro Professor of Environmental Law at the University of California, Los Angeles, and was acting administrator of the National Highway Traffic Safety Administration under President Biden. Thank you so much, Professor Carlson.

CARLSON: You're welcome. It was a pleasure to be here.

DOERING: After the Senate voted to revoke the California waivers, EPA issued a press release with this statement from Administrator Lee Zeldin, who said: “We are glad to see that Congress recognized the truth, that EPA’s California waivers are rules that would create a negative impact on all Americans by driving up costs while limiting consumer choice and acted accordingly. This action, once signed by President Trump, not only prevents California from implementing their attempt at EV mandate actions but ensures that they can never do something similar again.” The full EPA press release is at the Living on Earth website, loe.org.

 

Links

Read Ann Carlson’s blog post about the Senate’s decision

See how your Senator voted in the decision to repeal California’s Clean Air Act waivers