On Friday, the Supreme Court overturned a long-standing legal doctrine in the US, making a transformative ruling that could hamper federal agencies’ ability to regulate all kinds of industry. Six Republican-appointed justices voted to overturn the doctrine, called Chevron deference, a decision that could affect everything from pollution limits to consumer protections in the US. 

Chevron deference allows courts to defer to federal agencies when there are disputes over how to interpret ambiguous language in legislation passed by Congress. That’s supposed to lead to more informed decisions by leaning on expertise within those agencies. By overturning the Chevron doctrine, the conservative-dominated SCOTUS decided that judges ought to make the call instead of agency experts. 

“Perhaps most fundamentally, Chevron’s presumption is misguided because agencies have no special competence in resolving statutory ambiguities. Courts do,” Chief Justice John Roberts writes in his opinion.