WASHINGTON — The Bush administration is arguing that unless the U.S. Supreme Court overturns a Utah case it has agreed to hear, federal courts will soon take over the Interior Department's role as day-to-day managers of public lands.

U.S. Solicitor General Theodore B. Olson filed a brief arguing that the 10th Circuit Court of Appeals erred when it sided with environmental groups in ruling that the Interior Department was not doing as much as required by law to protect wilderness-like areas in Utah from damage by off-road vehicles.

They brought their suit under a section of the Administrative Procedure Act that allows suing "to compel any agency action unlawfully withheld or unreasonably delayed." Olson argues the 10th Circuit improperly expanded that to allow review of the adequacy of an agency's ongoing management — not just whether it is acting at all.

Olson argues that a proper interpretation of the law should be that "although a court may direct an agency to act when action is clearly required by law, a court may not direct an agency how to act."

He said if the lower court decision stands, it "would invite the district court improperly to substitute its judgment and discretion for those of the agency." He argued, "Such judicial intrusion into the responsibility of the executive branch is inconsistent with the separation of powers under the Constitution."

Olson also said a 1990 Supreme Court ruling in Lujan v. National Wildlife Federation — about another section of the same law — also cautioned that environmental groups "cannot seek wholesale improvement of (an agency's) program by court decree, rather than in the offices of the Department or the halls of Congress, where programmatic improvements are normally made."

The new case, (Interior Secretary Gale) Norton v. Southern Utah Wilderness Alliance, is scheduled for oral argument before the Supreme Court on March 29, and the sides are in the process of filing written briefs. A response from environmental groups to the government's arguments is due later this month.

In the lower court decision, the Bureau of Land Management was ordered to manage Utah lands, which are being considered for formal wilderness designation, so that off-road vehicle use would not impair their wilderness values; to manage ORVs in accordance with land use plans; and to look at whether more environmental review of activities was needed because of ORV damage.

Olson argued the case essentially tries improperly to give goals and land-use plans of the Interior Department the same force as if they were statutory law.

He said that instead, "a land use plan is a fluid, process-oriented document" — and how well its goals are met are "contingent on available resources and competing priorities." He said courts should not impose their agenda and priorities instead of those of the administration.