Opinion editor's note: Editorials represent the opinions of the Star Tribune Editorial Board, which operates independently from the newsroom.

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Whether one admires or detests the modern conservative legal movement, it has become a strikingly successful example of a focused, decades-long campaign to bring about major change through the political process.

Having labored persistently for more than 50 years to reshape American jurisprudence — by populating courts with judges who interpret law mostly through the literal wording and original meaning of legal texts — the movement last week fulfilled the last of three overriding goals that inspired it.

The first two of those central aims involved today's conservative U.S. Supreme Court overturning long-lived precedents that had nourished long-lived controversy. In 2021 the high court overturned Roe v. Wade, returning abortion policy to the states. And in 2023 it largely outlawed race-based affirmative action programs in college admissions.

Last week's landmark concerned an issue less familiar and provocative to the general public — the excessive power, as many conservatives see it, of regulatory agencies, the "administrative state." But it too overturned a venerable, decades-old precedent, and its impact also could be sweeping and durable.

The abandonment of "Chevron deference," as last week's decision is often described, will add to the determination of the current court's critics to turn the tables on the conservative legal movement and work to transform the courts once again. That is altogether proper — democracy in action. But meanwhile, like all of the court's decisions, the Chevron ruling for now is the law of the land. Understanding it and adjusting to it in constructive ways are also duties of American institutions and citizens.

"Chevron deference" was a legal rule created by the Supreme Court's 1984 decision in Chevron v. National Resources Defense Council. Simply put, the rule instructed courts to defer to the legal interpretations of executive branch agencies whenever a law giving an agency regulatory powers was "ambiguous" on a point in dispute and the agency's resolution was "reasonable" — even if the court thought the agency's reading of the law was wrong. In the cases that brought the doctrine before the court last week, deep-sea fishing firms protested having to pay the costs of carrying legally required inspectors on their boats. The law had not made clear how those costs were to be covered.

For 40 years, under the Chevron doctrine, courts had deferred to agency decisions in such matters — and in thousands of other situations far more complex, technical and momentous. Environmental, medical and financial disputes with large social and economic significance have been decided under its framework.

Champions of the Chevron rule — who years ago included prominent conservatives such as the late Justice Antonin Scalia — have argued that courts' deference to agency regulators empowers experts to make specialized judgments they are better equipped for than are judges, while helping courts resist the temptation to meddle in policy questions properly left to Congress and the agencies it creates to carry out its will. Detractors argued that judges are the real experts when it comes to discerning the meaning of laws and the rights of citizens. And besides, said foes of the administrative state, the Constitution guarantees Americans with a beef against government a day in court before an independent judge, not just a bureaucratic hearing before another employee of the agency they're fighting.

The underlying debate at work here, about the proper boundaries separating the powers of Congress, presidential administrations and the judiciary, is as old as America, and it has evolved over time with changes in the political environment. Four decades ago, conservatives worried more about overreaching activist courts; liberals decried the imperial presidency. To some degree, they've swapped concerns.

A majority of six conservative justices overruled the Chevron doctrine last week. Henceforth, "courts may not defer to an agency interpretation of the law simply because a statute is ambiguous," wrote Chief Justice John Roberts, while noting that views of agency experts are "entitled to 'great weight.' " He added assurances that "the Court does not call into question prior cases that relied on the Chevron framework."

The concern is legitimate that many thousands of previously settled regulatory issues could be reopened by this ruling. Roberts noted that exceptions and qualifications to the Chevron doctrine have proliferated over the years, forcing the court "to clarify the doctrine again and again," producing "dizzying" confusion.

Meanwhile, Justice Elena Kagan, writing for the dissenters, scoffed at Roberts' soothing words about past rulings. "The majority's decision," she wrote, makes a "laughingstock" of stare decisis — the principle that courts should respect precedent. It "will cause a massive shock to the legal system, casting doubt on many settled constructions of statutes," she added.

We hope she's mistaken. Certainly, preventing the kind of regulatory chaos Kagan fears will be a major responsibility for this bold conservative court — even if doing so requires some further "clarifying" in the years ahead. The "respect" Roberts says judges should continue to show for executive branch expertise must become a reality, lest regulators grow skittish about fulfilling the duties Congress gives them to safeguard public health, environmental quality, financial integrity and much else.

Importantly, Congress, too, is being challenged with this watershed separation of powers ruling. An effort to more carefully draft laws that better define the boundaries of agency powers and discretion could restore accountability to elected officials, inspire more lawmaking compromise, and help keep both regulators and courts in their proper domains.