RENO --  Pershing County officials are asking a judge to dismiss a lawsuit filed by Burning Man organizers who say a new county festival ordinance is unconstitutional and could put the annual counter-culture event in Nevada's Black Rock Desert out of business.

Leaders of Black Rock City LLC say the new $1.50-per-head fee to cover law enforcement costs at events with 1,000 or more people would force Burning Man to pay the county $600,000 or more — up from $175,000 in 2010.

They said in a lawsuit filed in district court in Lovelock on Aug. 16 the ordinance violates their First Amendment rights by allowing Pershing County deputies to regulate behavior considered "obscene, indecent, vulgar or lewd."

They maintain the county has no jurisdiction over the event held on federal land 110 miles north of Reno — about 52,000 people attended this year — and argue the county is singling them out in a discriminatory way.

But Pershing County said in the motion for dismissal on Tuesday that the ordinance that goes into effect in 2013 applies to all events in the county uniformly.

Pershing County District Attorney Jim Shirley told the Reno Gazette-Journal that Burning Man's contract mandates that events comply with state laws and that the ordinance falls under state law. He said the costs are consistent with what other counties charge for a comparable number of officers.

Burning Man spokeswoman Megan Miller told the newspaper the motion to dismiss is a standard legal procedure and "does not state any valid grounds for dismissing our complaint."

"Pershing County engaged in activity that violated the First Amendment, breached their contact with Burning Man and imposed excessive fees on the Burning Man event," she said.