Colorado leaders are furious after the Trump administration suddenly revoked the 2009 EPA “endangerment finding” that declared greenhouse gases a threat to public health. State officials warn the move will cost families billions at the pump, worsen air quality, and invite immediate lawsuits.

The decision, announced February 13, 2026, wipes out the legal foundation for almost every major climate rule of the past 17 years.

Trump White House Claims Trillions in Savings

President Trump called the old finding “ridiculous” and promised Americans will save “trillions” overall. The White House says new cars will drop almost $3,000 in price without what it calls burdensome green mandates.

Senior administration officials told reporters the repeal ends fuel-efficiency and emissions standards imposed on vehicles from 2012 through 2027 and beyond.

The 2009 endangerment finding has been the legal backbone for every vehicle emissions rule since the Obama administration. Without it, those standards lose their legal force.

Colorado Energy Chief: “This Will Cost Us Billions in Gas”

Will Toor, executive director of the Colorado Energy Office, did not hold back.

“The science has only gotten stronger,” Toor said. “Greenhouse gases are warming the planet and hurting people. Revoking the finding is pure politics, not science.”

Toor pointed to federal studies showing the Obama-era rules saved drivers money at the pump through better mileage.

“Coloradans will now pay billions more for gasoline every year,” Toor warned. “This is a direct transfer from family budgets to oil companies.”

He called the move “a lose-lose-lose” for public health, household wallets, and the state’s economy.

Attorney General Weiser: See You in Court

Colorado Attorney General Phil Weiser issued a blistering statement within hours.

“There is zero legal or scientific justification for this rollback,” Weiser said. “We will sue and we expect to win, just as states did the last time Trump tried this.”

Weiser successfully defended Colorado’s clean-car standards during Trump’s first term. His office is already preparing litigation with California and at least a dozen other states.

Governor Polis: Kids and Seniors Will Breathe Dirtier Air

Governor Jared Polis released an equally sharp response.

“Every parent knows tailpipe pollution hurts kids’ lungs,” Polis said. “Rolling back proven protections creates chaos for families and businesses exactly when Colorado is leading in clean energy jobs.”

Polis highlighted the state’s booming electric-vehicle sector and charging network, both built on the certainty provided by the endangerment finding.

Public Health Department: “We Won’t Back Down”

Jill Hunsaker Ryan, executive director of the Colorado Department of Public Health and Environment, promised the state will keep pushing cleaner choices no matter what Washington does.

“Vehicle exhaust remains one of our biggest sources of climate pollution and smog,” Hunsaker Ryan said. “Colorado will continue protecting our air, our snowpack, and our kids’ future.”

What the Endangerment Finding Actually Did

The 2009 determination came after the Supreme Court ruled in Massachusetts v. EPA (2007) that greenhouse gases could be regulated as pollutants under the Clean Air Act if they endangered public health or welfare.

Every major vehicle emissions standard since then rests on that finding.

Real-world results under the rules:

• Average new vehicle fuel economy rose from 25 mpg in 2009 to over 40 mpg today
• Drivers saved an estimated $6,000 over the life of a vehicle in fuel costs
• Oil consumption dropped by millions of barrels per day
• Colorado’s famous brown cloud over Denver has visibly thinned

Transportation remains the largest source of greenhouse gases in both Colorado and the nation.

Next Steps and Timeline

The EPA published the revocation notice on February 14, 2026. A 60-day public comment period begins immediately.

Colorado officials say they will file suit the moment the rule is final, likely this spring.

Legal experts widely agree courts upheld the original finding multiple times during Trump’s first term. Most expect judges to block the repeal again unless the administration produces new science, something it has not done.

Colorado continues to follow California’s strict vehicle standards, which state law allows regardless of federal rules. Fourteen other states do the same, covering roughly 40 percent of the U.S. auto market.

The fight over clean air has only just begun, again.

What do you think: Will Colorado and other states stop this rollback in court, or is this the end of federal climate rules for cars? Drop your take in the comments and use #ColoradoFightsClimateRollback if you’re sharing on social media.