WASHINGTON — The Supreme Court issued a landmark decision on Friday, overturning a longstanding precedent that has been a focal point of conservative critique for allegedly bolstering "deep state" bureaucracy.

In a pivotal ruling involving a challenge to fisheries regulation, the Court consigned the 1984 decision in Chevron v. Natural Resources Defense Council to history. Chevron had established the principle of judicial deference to federal agencies' interpretations of ambiguous statutes, granting significant regulatory latitude to bureaucrats.

Chief Justice John Roberts, writing for the 6-3 majority along ideological lines, declared, "Chevron is overruled." He emphasized that henceforth, courts must exercise independent judgment in assessing whether agencies have stayed within their statutory authority, thereby curbing the deference previously accorded to agency interpretations.

Roberts clarified that the decision does not invalidate prior Chevron-based rulings but instructs lower courts against reflexively deferring to agency interpretations solely due to statutory ambiguity.

Justice Elena Kagan authored a forceful dissent, characterizing the decision as an unprecedented assertion of judicial authority over established administrative practices. She argued that overturning Chevron places federal judges at the forefront of administrative decision-making across various regulatory domains, potentially undermining agencies' technical expertise and scientific knowledge.

"The ruling subjects agencies to heightened judicial scrutiny on issues ranging from environmental conservation to healthcare and technological innovation," Kagan lamented. "It raises fundamental questions about the development of future regulatory frameworks addressing critical national concerns such as climate change."

Initially hailed as a triumph for deregulation during the Reagan era, Chevron had provided both Republican and Democratic administrations with flexibility in navigating regulatory complexities. However, over time, critics on the right contended it excessively enlarged bureaucratic discretion.

Progressive groups and environmental advocates had staunchly defended Chevron, arguing it facilitated adaptive responses to environmental challenges like climate change. Vickie Patton, general counsel of the Environmental Defense Fund, condemned the Court's decision, cautioning it could weaken safeguards for clean air, water, and climate policies.

The case centered on a federal rule mandating fishing vessel operators in New England to fund data collection for fishery conservation. Challengers contended the National Marine Fisheries Service lacked statutory authority under the Magnuson-Stevens Fishery Conservation and Management Act of 1976 to impose such financial obligations.

Roman Martinez, representing the challengers, praised the Court's decision as pivotal in safeguarding separation of powers and curbing what he termed "unlawful agency overreach."

The fisheries dispute forms part of a broader trend in the current Supreme Court term, where justices scrutinize federal agency powers in response to challenges driven largely by business interests and conservative legal advocates. The Court's conservative majority, bolstered by three Trump appointees, has played a key role in reshaping judicial perspectives on administrative law.

Prior to Chevron, the Supreme Court had already restricted federal agency authority in cases involving President Biden's student loan debt relief plan, Covid vaccination mandates for larger businesses, and EPA regulations on power plant emissions. These decisions invoked the "major questions doctrine," requiring explicit congressional authorization for sweeping national policies.

As the legal landscape evolves, the Supreme Court's Chevron decision sets a precedent that could reshape regulatory governance dynamics, highlighting the ongoing tension between judicial oversight and administrative discretion in shaping national policy responses.