NEW ORLEANS >> Millionaire real-estate heir Robert Durst returns to court Thursday, where his attorneys planned to argue that the FBI searched his room illegally and police covered this up in statements used to get an arrest warrant on Louisiana weapons charges.

Durst has waived extradition to Los Angeles, where he faces a murder charge. His lawyers say they want to get him there to fight that charge.

He was scheduled for a hearing Thursday before Magistrate Harry Cantrell on charges of possessing a firearm after a felony conviction and illegally possessing a firearm along with an illegal drug.

In a motion filed Tuesday, Durst’s attorneys argue that FBI agents “rummaged” through the 71-year-old man’s hotel room without a warrant before he was arrested.

Orleans Parish district attorney’s investigator Jim O’Hern testified at Durst’s bail hearing that he helped Los Angeles detectives get the warrant on which Durst was arrested early March 15, a Sunday. An FBI agent had inventoried Durst’s belongings in his hotel room the afternoon of March 14 and a judge signed the warrant about 2 a.m. the next day, he said.

The affidavit used to get the warrant states Los Angeles police and New Orleans prosecutors got a warrant, then searched the room and found the gun and drugs, according to the Tuesday motion.

Durst was arrested last month at the J.W. Marriott hotel in New Orleans. Items recovered from his hotel room included a revolver and about 5 ounces of marijuana, according to court records.

A sworn statement supporting the warrant “contains a material misrepresentation designed to cover up the FBI’s unlawful, warrantless search of Mr. Durst’s hotel room,” according to a copy of the motion provided to The Associated Press by Durst’s lawyers.

Durst’s attorneys also have asked the judge to subpoena Fox News Channel’s Jeanine Pirro, a former New York prosecutor who investigated Durst in connection with the disappearance of his first wife in 1982, and all video surveillance for March 14 and 15 from the Marriott and Los Angeles Police Department.

Los Angeles police, who have a warrant accusing Durst of killing his friend and spokeswoman Susan Berman in 2000 to keep her from talking to Pirro’s investigators, and the FBI did not immediately respond to requests for comment Wednesday. Louisiana State Police referred requests for comment to the Orleans Parish District Attorney’s Office. That office does not comment on open cases or investigations, spokesman Chris Bowman said.