Chevron deference

Perhaps even more significant have been its dramatic curbs on federal regulation in the form of “the major questions doctrine” and end to so-called Chevron deference, not to mention its stratospheric advancement of executive power in Trump v.

In the second ruling, issued in July, the court abandoned the 40-year-old “Chevron deference” precedent, under which federal courts tended to defer to agency interpretations of statutes that were found to be legally ambiguous, if the interpretations were “reasonable.”

It states that regulations that courts approved through Chevron deference are grandfathered — so overturning them will still require the full APA treatment.

The ruling, handed down on Thursday from three Republican judicial appointees, cited the Supreme Court’s recent overturning of the long-held precedent of "Chevron deference," which asked lower courts to defer to federal agencies' interpretation of the law.

Federal agencies suffered a blow to their authority in July when the conservative majority of the Supreme Court — which Trump cemented with his appointees — overturned the “Chevron deference.”