Real estate scion Robert Durst is facing a wrongful death suit from the family of his first wife, who disappeared in 1982 and has never been found. 

The New York Post reported that James McCormack, brother of Kathleen Durst, filed notice of his intended suit in Manhattan Surrogate's Court Thursday. 

McCormack told the Post that he gave up his longstanding belief that Kathleen was still alive after viewing HBO's six-part documentary "The Jinx: The Life and Deaths of Robert Durst" earlier this year. The documentary examined Durst's role in three possible deaths: Kathleen's; Durst's friend and onetime spokeswoman Susan Berman; and the death and dismemberment of a neighbor in Galveston, Texas in 2001.

The series was highlighted by Durst's apparent confession to all three murders in the final moments of the last episode. After being confronted with evidence of his culpability in Berman's death, Durst walked off camera to use the bathroom while still wearing a live microphone. While using the facilities, Durst whispered, "What the hell did I do? Killed them all, of course."

"Bob uttered the words, 'Killed them all of course.' He didn’t say, he killed one, or two, he said he killed them all," McCormick, 70, told the Post. "I turned to my ex-wife and shed a tear and finally there was closure. The next step is justice."

Durst was arrested in New Oreleans in connection with Berman's murder on the eve of the premiere of the six-part documentary's finale. He is currently awaiting trial in Louisiana on a federal charge that he illegally possessed a .38-caliber revolver after being convicted of a felony. That trial is due to begin Jan. 11.

"Anyone can file a lawsuit," Durst’s lawyer Dick DeGuerin, told the Post, "but to prevail in the lawsuit, you have to have evidence, and there is no evidence other than this docudrama that was designed first and foremost to win an Emmy." 

Durst is an estranged member of the family that runs the Durst Organization, which oversees 1 World Trade Center in Lower Manhattan, among other valuable properties.

The Associated Press contributed to this report.

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