LOS ANGELES (CBSLA.com) — A judge in the murder trial of real estate heir Robert Durst agreed Friday to allow early testimony from at least two witnesses in the multimillionaire’s upcoming murder trial.

Los Angeles County Superior Court Judge Mark Windham ruled that the witnesses can give their testimony on Feb. 14, before the trial even begins.

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Windham found that prosecutors have provided evidence that one of the witnesses, whose name has been kept secret, could be in danger. The other witness is being allowed to testify early because he is 85 years old.

“Let me be clear. Let me be succinct. That man kills witnesses. That’s what he does,” prosecutor John Lewin said. “This is no puffery by the district attorney’s office.”

The testimony will not be used if the witnesses are available to testify during Durst’s trial, which has not been scheduled.

So far, there are four witnesses on the list. Two are considered secret witnesses, which the defense objected.

“We don’t want to be shadowboxing. We don’t want to be simply fighting against something we don’t know,” defense attorney Dick Deguerin argued.

The 73-year-old has pleaded not guilty to one count of first-degree murder in the 2000 fatal shooting of his friend, Susan Berman.

Prosecutors contended that Durst killed her because she was prepared to speak with police about the 1982 disappearance of his wife, Kathleen Durst.

Allowing the early testimony over fears of witness danger would be to presume that Durst killed his wife and Berman, and there’s no evidence involving either, Deguerin contended.

Durst’s attorneys also have argued that their client is harmless because he is frail and behind bars. They have accused the prosecution of trying to litigate the case in the news media.

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“We’re in a very complicated case with experienced lawyers who are not going to sit by and say it’s OK to steamroll Mr. Durst,” said David Chesnoff, another Durst attorney.

Prosecutors are taking an aggressive approach in publicly laying out their theory of the case before knowing if it will go to trial.

The defense has objected to some of the information prosecutors have revealed, including a transcript and recording of a nearly three-hour interrogation of Durst following his arrest in New Orleans in 2015.

One of the witnesses prosecutors will question on Feb. 14 is a doctor who may have been the last person to speak with Kathleen Durst. No charges have ever been brought in the suspected killing of Durst’s first wife, whose body has not been found.

Lewin may also call witnesses to the killing of Durst’s neighbor in Texas. Durst was acquitted of murder in the case but convicted of tampering with evidence and jumping bail.

Durst fled to Texas after learning the investigation into his wife’s disappearance had been reopened in fall 2000, Lewin said.

Berman, who had served as an unofficial spokeswoman for Durst, was killed weeks later in her Los Angeles home before she was supposed to speak with police about that investigation.

Durst, an estranged member of a New York real estate empire, became a national name when HBO aired the documentary “The Jinx,” which followed his life and cast suspicion on him involving several crimes.

FBI agents tracked Durst to a New Orleans hotel on the eve of the finale of “The Jinx.” Durst was formally arrested early on the day of the broadcast, before viewers saw him in a washroom, still wearing a live microphone and muttering, “There it is. You’re caught! What the hell did I do? Killed them all, of course.”

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