Tucson had already broken its record for first 100-degree day by nearly a month when Arizona Attorney General Kris Mayes announced she was suing President Donald Trump over his decision to rescind the Environmental Protection Agency’s 2009 Endangerment Finding, a seminal declaration that labeled carbon dioxide, methane and other greenhouse gases threats to public health and welfare.
The Trump administration announced in February that it would repeal the finding, which has been used to regulate greenhouse gas emissions from cars, trucks and power plants.
Trump called it the “largest deregulation in American history” and promised that getting rid of it would make cars cheaper.
Mayes’ lawsuit — joining a coalition of 24 states and several cities challenging the decision — comes with a twist: A 2010 law signed by then-Gov. Jan Brewer gave the state Legislature the power to regulate — or not — greenhouse gases.
They’ve so far chosen the latter, which means Arizona’s laws default to federal standards set by the EPA.
So even if Mayes wins, Arizona could still lag behind heavily regulated states like California — because it has never built its own independent climate framework.
Arizona Attorney General Kris Mayes.
We called Mayes last week to learn more about why she filed the lawsuit.
It’s not lost on the former Arizona Corporation Commissioner why her office had to get involved — the EPA’s 2009 Endangerment Finding is the foundation of how the federal government (and most states) set limits on climate pollution.
“The 2009 Endangerment Finding by the EPA is a cornerstone of how we are fighting climate change in this country and in Arizona,” Mayes told us. “All you have to do is look at the extreme temperatures that we are seeing here in Arizona this month to understand how catastrophic this decision by the federal government is going to be.”
The decision by the EPA 17 years ago was thoroughly vetted in federal court and has shaped vehicle emissions standards and rules governing power plants, anchoring regulation to scientific findings.
In 2010, Brewer signed into law a measure that barred state regulators from adopting or enforcing greenhouse gas regulations unless required by federal law.
Mayes said the 2010 law didn’t factor into her challenge, telling us that greenhouse gases affect the entire country and the entire Southwest.
“Anything that impacts the ability of Arizona, New Mexico, California, Utah, Colorado to address greenhouse gases, frankly, the whole country is going to negatively impact Arizona,” she said. “This is something that obviously states can help address (in each state), but we need this endangerment finding to address it on a nationwide basis.”
And while the Trump administration labels the rule as bureaucratic overreach, it is also arguing that the U.S. Supreme Court was wrong in 2007 when it ruled the EPA had authority to regulate greenhouse gases under the Clean Air Act in Massachusetts v. EPA.
The landmark ruling ordered the EPA to make the endangerment determination, which became federal policy in 2009.
“Obviously, the Trump administration is trying to do an end run against what the Supreme Court already did,” Mayes told us.
While the lawsuit winds its way through the courts, Mayes keeps fighting for the environment.
She filed a new lawsuit against the Arizona Corporation Commission over its repeal of renewable energy standards yesterday.
Hallmarks of a cult: A woman is suing the leaders of Global Communications Alliance, the spiritual compound near Tumacacori, Dan Shearer reports for the Green Valley News. The woman’s parents brought her to the compound as a baby in 1996 and she fled in 2015. She claims the compound’s leader, Anthony Joseph Delevin, AKA Van of Urantia, engineered a system to break down children and adults, then isolate them and make them “dependent on the very people harming them.” Delevin and his fellow elders also used “sexualized violence” to keep people in line and forced every member to surrender all their money when they joined.
Not letting go: City and state officials across Arizona quickly got rid of references to César Chávez after he was accused of decades of sexual abuse. His legacy is a little more complicated in Yuma County, where he grew up, Sisko J. Stargazer reports for KAWC. The Gadsden School District is considering whether to change the names of an elementary and middle school, but several of the speakers at a public meeting said they doubted the accusations of sexual abuse and urged the board to focus on Chavez’s contributions to the farm workers movement, which at least one of them had lived through.
At today's #nokings in Tucson. Ukelele Fight Club Tucson! @maddow.bsky.social
— John Clark (@renbear67.bsky.social) 2026-03-28T17:12:27.509Z
Abortion battles ahead: Tucson-area Republican Rep. Rachel Keshel is pushing a crackdown on abortion-inducing drugs like mifepristone, per Capitol scribe Howie Fischer. Under Keshel’s HB2364, which is awaiting a Senate vote, providing those drugs would bring a felony charge and 2.5 years in prison for healthcare providers and pharmacists, as well as manufacturers and suppliers. All of that is modeled after a Texas law, but Keshel made her own addition: A woman who orders those drugs without consulting a doctor would face a misdemeanor charge and six months in jail. Democratic lawmakers, including Tucson-area Rep. Stephanie Stahl Hamilton, pointed out that voters approved Prop 139 to protect abortion rights two years ago. And Gov. Katie Hobbs is sure to veto the measure, should it reach her desk.
Opening Day, 1951: The smell of freshly mowed outfield grass is in the air as Major League Baseball kicks off another season. Cronkite News’ Austin Gibbs takes a turn down memory lane to revisit the forgotten Cactus League stadiums in Arizona where legends like Joe DiMaggio and Mickey Mantle used to play.
Don’t let political newsletters go the way of those forgotten stadiums. Support local journalism.
Put your finger on the pulse: As Tucson officials get feedback from residents about the city’s plan to regulate data centers, they’re making 89 pages of written feedback publicly available, which means you can read what your neighbors wrote and get a sense of how the next big fight over data centers might play out. And if you want to see how local officials are dealing with the surge in data centers in the West, check out Wyoming Public Radio’s rundown of county-imposed moratoriums from the Idaho Panhandle to Logan County, Colorado.
It must be election season because Joe can’t even go to the drug store without running into something tied to a congressional race.
He spotted the official CyberTruck of Congressional District 6 GOP candidate Daniel Butierrez at a CVS yesterday, though he didn’t see the candidate inside.
Butierez, by the way, is at least the second Republican congressional candidate in Arizona to rock a CyberTruck as part of his campaign.
As we noted yesterday, Joe also spotted Democratic Congresswoman Adelita Grijalva and Congressional District 6 Democratic candidate JoAnna Mendoza at Saturday’s #NoKings rallies in Tucson.
Hopefully, he’ll run into Republican U.S. Rep. Juan Ciscomani later this week to finish his Southern Arizona Congressional delegation (and challengers) bingo card.