Texas – U.S. Senator Ted Cruz has joined Senator Cynthia Lummis in filing an amicus brief supporting the Environmental Protection Agency’s decision to rescind a key 2009 climate regulation known as the Greenhouse Gas Endangerment Finding, which underpins federal vehicle emissions standards.
In the filing, Cruz and Lummis argue that the EPA exceeded its authority when it originally established greenhouse gas regulations under the Clean Air Act. They claim the agency used powers not clearly granted by Congress and that the rules amounted to a major policy decision that should not have been made by a federal agency alone.
The senators rely heavily on the “major questions doctrine,” a legal principle that requires Congress to clearly authorize federal agencies when they take actions with large economic or political consequences. They argue that greenhouse gas vehicle regulations affect “virtually every sector of the economy” and therefore require explicit congressional approval.
The brief also states that the 2009 EPA rule effectively pushed a transition away from gasoline and diesel vehicles toward electric vehicles without clear legislative authorization. Cruz and Lummis argue that such a shift represents a fundamental transformation of the transportation sector that only Congress has the power to approve.
According to the filing, the EPA correctly determined that it lacked the necessary congressional authority to impose the original emissions standards. The senators therefore support the agency’s decision to rescind the 2009 endangerment finding and related vehicle emissions rules, arguing that doing so restores constitutional separation of powers.
The brief concludes that the court should uphold the EPA’s reversal of the rule.






