Attorneys for snowmobile manufacturers, winter resorts and other tourism-related ventures have asked a federal judge to permanently lift a snowmobile ban in Yellowstone and Grand Teton national parks so the businesses can have peace of mind about their survival.

U.S. District Judge Clarence Brimmer heard the request last week from the businesses, joined by the states of Montana and Wyoming. Their lawyers said action by Brimmer would prevent another federal judge, in Washington, D.C., from reinstituting the 2001 ban and creating economic uncertainty for the area.

"This thing keeps showing up," Wyoming lawyer Jay Jerde told the judge. The ban "has not been struck down by any court or ruled invalid by any court."

The Clinton administration ban, to take effect last winter, was set aside in early 2003 by the National Park Service to settle a lawsuit filed by snowmobile makers. Under the agreement, new rules were drafted to allow a limited number of snowmobiles inside the parks.

Brimmer's Washington colleague, U.S. District Judge Emmet Sullivan, overturned the regulations and ordered the ban to begin this year. Brimmer set aside Sullivan's decision in February. The Park Service now is planning new regulations to cover the next three winters, which lawyers for the federal government and environmental groups said should be allowed to continue.

"The merits of that rule need to have their day in court," argued Abigail Dillen of the Bozeman, Mont., office of Earthjustice, representing the Greater Yellowstone Coalition.

Both sides agreed that if Brimmer strikes down the 2001 rule, the Park Service would probably have to revert -- at least temporarily -- to its 1983 rule allowing unregulated snowmobiling. Brimmer was clearly uncomfortable with that option, given the consensus that limits on the snowmobiles are necessary to protect the park's wildlife and reduce noise.

If the new regulations are challenged in court, Sullivan might again invoke the ban, said William Horn, representing the International Snowmobile Manufacturers Association.

Lawyer Keith Burron, representing Montana, said the state feels strongly about protecting Yellowstone's natural resources but that the effects on businesses were not fully considered.

"There are some extreme gateway community impacts," he said. "That's why Montana is in this case now."

Andrew Emrich, a lawyer with the Justice Department, argued that the Park Service should be allowed to continue working on the new rules.

Brimmer pressed Emrich to make sure all parties have a chance to participate. Emrich said they would.

Brimmer criticized Sullivan several times for asserting jurisdiction in a case that began in Wyoming in 2000.

"I think this appearance of quarreling or competition between two U.S. district courts is most unseemly," Brimmer said. "He shouldn't have done it because this court had jurisdiction in the first place."

Brimmer said he would issue a decision later, then told Yellowstone officials in the courtroom that he has "no intention of supplanting your jurisdiction in running the park."