Robert A. Durst, the troubled scion of a New York real estate family, may be one step closer to being transferred to Los Angeles to answer murder charges.

Mr. Durst, who has been in custody in New Orleans on a gun charge since March, lost a motion on Tuesday to have evidence in the case dismissed. His lawyers have repeatedly said they were eager to dispose of the gun charge so he can respond to claims that he murdered a onetime confidante 15 years ago in Los Angeles.

Given the ruling on the evidence, Mr. Durst, who is facing a maximum of 10 years in prison on the gun charge, can appeal, proceed to trial next year, or bargain with prosecutors for a lighter sentence.

Dick DeGuerin, a lawyer who leads Mr. Durst’s defense team, said he was disappointed by the decision.