What Is the Congressional Review Act, and How EPA Is Using It Now
A 1996 law lets Congress erase agency rules with a simple vote, and this month it's aimed squarely at California's authority to write its own tailpipe standards.
On June 12, the Environmental Protection Agency sent four rules to Capitol Hill that had nothing to do with a floor vote anyone was expecting that week. The rules governed California's authority to set its own tailpipe emission standards for cars, trucks and lawn equipment, some of it dating back to 2009. The mechanism EPA used to put them in Congress's hands is a 1996 statute most Americans have never had reason to learn: the Congressional Review Act.
"EPA is accountable to Congress, but most importantly we must be accountable to the American people," EPA Administrator Lee Zeldin said in the agency's announcement. "It is important for EPA to fulfill our statutory obligation to submit these California waivers to Congress for their review pursuant to the law."
What the Congressional Review Act Actually Does
The CRA lets Congress erase a finalized federal agency rule with a simple joint resolution. No rewrite, no replacement policy, just a vote that the rule "shall have no force or effect," as constitutional law site usconstitution.net has laid out. It's a narrow tool by design. The resolution needs only a simple majority in both chambers and, critically, cannot be filibustered in the Senate. Congress built itself a fast lane specifically for reviewing agency rulemaking.
There's a sting built into the back end, too: once a rule is disapproved, the agency generally can't issue a new one that's "substantially similar" without new authorization from Congress. That ambiguity, nobody has ever defined exactly how similar is too similar, gives a single disapproval vote outsized, long-tail power over an entire policy area.
The clock matters as much as the vote count. Under the CRA, members of Congress have roughly 60 session days after a rule is formally submitted to introduce a disapproval resolution. A "lookback" provision extends that window when rules are submitted late in a session, letting a new Congress reach back and disapprove a predecessor's late-term rules. That's why CRA activity tends to spike right after control of government changes hands.
What Counts as a "Rule" Under the Act, and Why That's the Fight Here
The California waivers expose the CRA's blurriest edge. The Clean Air Act lets California request "preemption waivers" from EPA to set stricter vehicle-emission standards than the federal floor, and lets other states adopt them too. For decades, EPA didn't treat those waiver decisions as CRA "rules" at all. They were case-by-case determinations, not generally applicable regulations.
That changed in 2025. According to a legal alert from Holland & Knight, both the U.S. Government Accountability Office and the Senate Parliamentarian had concluded the waivers didn't qualify as CRA rules at all. Congress pushed the disapproval resolutions through anyway, and President Trump signed them into law in June 2025. California sued. That case is still pending in federal court in California.
The four waivers EPA transmitted this June go further than last year's round. They include California's 2009 greenhouse-gas standards for passenger vehicles, the Advanced Clean Cars I program, its 2022 reinstatement, and, for the first time, the Small Off-Road Engine amendments covering lawn and garden equipment, a category never previously pulled into a CRA fight. On June 22, California filed a second lawsuit, this one in Washington, D.C., seeking to block the new submissions entirely.
| Waiver Sent to Congress | What It Currently Allows |
|---|---|
| Advanced Clean Cars I (ACC I) | California vehicle-emissions rules stricter than federal standards |
| 2022 Reinstatement of ACC I | Restored ACC I after it was revoked in Trump's first term |
| Small Off-Road Engine (SORE) Amendments | Emission limits pushing lawn and garden equipment toward electrification |
| 2009 Greenhouse Gas Standards | California's authority to set its own vehicle GHG limits |
Why Congress Reaches for This Tool So Often Now
The CRA sat mostly dormant for two decades. Data compiled by George Washington University's Regulatory Studies Center shows that of the more than 461 disapproval resolutions introduced in Congress between 1996 and 2024, only a small fraction ever became law, and EPA has been the single most frequent target, with its rules challenged more than 70 times. Nearly every spike in CRA activity lines up with a change in the party controlling the White House, when an incoming Congress uses the lookback window to reach back into the outgoing administration's final months.
What's shifted, researchers at the GWU center noted in an April analysis, is that the tool once seen mainly as a way for an incoming administration to erase a predecessor's "midnight regulations" is now being used in less predictable ways: against older rules, against novel categories of agency action, and against determinations, like California's waivers, that were never obviously "rules" to begin with. It rhymes with how a pocket rescission lets the executive branch sidestep Congress on spending. Both are an executive branch and a Congress each testing how far a narrow statutory tool can stretch before a court says it snaps.
Congress now has until roughly late summer to act on the four new waivers, assuming the courts don't intervene first. If lawmakers pass disapproval resolutions and the president signs them, California's authority to set its own tailpipe rules for those four categories, some of it two decades old, disappears, and the state's ability to write a replacement will run straight into that "substantially similar" wall the statute never bothered to define.
