A divided Supreme Court on Wednesday declined a chance to overrule two longstanding precedents that make it easier for government agencies to defend their regulations from legal challenges in cases about the environment, health care and consumer protection.

The court instead used the case to further outline its doctrine on when judges should defer to an agency’s interpretation of its own regulation when that regulation is otherwise ambiguous. All the justices agreed to send the case back to a lower court for reconsideration.

But four justices on the conservative wing of the court expressed that they would have preferred to get rid of the doctrine in part because it gives agencies too much power to shape the law and how it is enforced and interpreted — casting doubt about how long it will last.

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The same concerns with the doctrine have been echoed by Republicans in Congress. Texas Republican John Ratcliffe, a member of the House Judiciary Committee, introduced a bill with 20 GOP co-sponsors that would modify the scope of review for agency actions to eliminate deference to the agency’s interpretation. Nebraska Republican Ben Sasse introduced similar legislation in the Senate that has 12 GOP co-sponsors.

Justice Elena Kagan, in announcing the court’s judgment from the bench, said that the Supreme Court’s doctrine was based on a presumption that Congress would want a court to defer to an agency’s view — since an agency would be the most appropriate interpreter of its own rules.

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That doctrine is called Auer deference or Seminole Rock deference after two cases that shaped it: Auer v. Robbins in 1997 and Bowles v. Seminole Rock & Sand in 1945.

Kagan wrote for the court that it is sometimes appropriate and sometimes not. “Auer deference retains an important role in construing agency regulations,” she wrote. “But even as we uphold it, we reinforce its limits.”

Kagan said from the bench that courts must retain the ability to check abuses of agency power. “That’s one reason we’ve taken care today to reinforce the limits of Auer deference, and to emphasize the critical role courts retain in interpreting rules,” she said. “But it’s no answer to the growth of agencies for courts to take over their expertise-based, policymaking functions.”

Justice Neil M. Gorsuch wrote separately to call Wednesday’s ruling “more a stay of execution than a pardon” for an Auer doctrine that “emerges maimed and enfeebled — in truth, zombified.”

“If today’s opinion ends up reducing Auer to the role of a tin god — officious, but ultimately powerless — then a future Court should candidly admit as much and stop requiring litigants and lower courts to pay token homage to it,” Gorsuch wrote.

The opinion also leaves open a question for future challenges to another, more well-known type of doctrine that has judges defer to agency interpretations of federal laws. That is called Chevron deference after the 1984 decision Chevron U.S.A. v. Natural Resources Defense Council Inc.

Chief Justice John G. Roberts Jr., who joined the court’s liberal wing to leave the precedents in place, wrote separately to add that issues about agency interpretations of their own regulations “are distinct from those raised in connection with judicial deference to agency interpretations of statutes enacted by Congress.”

“I do not regard the Court’s decision today to touch upon the latter question,” Roberts wrote.

In the case Wednesday, a Marine who served in the Vietnam War challenged a VA decision about service-connected disability benefits for post-traumatic stress disorder, and whether some new documents are “relevant” to the decision.