Real estate heir Robert Durst was arrested Saturday in New Orleans on murder charges just before the dramatic conclusion of the HBO documentary series, "The Jinx: The Life and Deaths of Robert Durst."

In the finale that aired Sunday night, Durst could be heard mumbling on a hot mic, "What the hell did I do? Killed them all, of course."

Durst, 71, was arrested by FBI agents at a J.W. Marriott hotel for the 2000 murder of Susan Berman in her Beverly Hills, Calif. home, the FBI said. 

Durst has also been linked to the disappearances of two other people, including his wife in 1982. Berman became a spokesperson for Durst and was murdered just days before police were going to interview her about Kathie Durst's disappearance.

Durst has waived extradition and will now return to California. 

"He's maintained his innocence for years," Durst's lawyer, Chip Lewis said. "Nothing has changed."

In addition to the apparent confession, HBO's filmmakers challenged Durst on a handwritten note that was sent to Beverly Hills Police at the time.

The anonymous letter told police they would find "a cadaver" in Berman's home.

The handwriting in the letter bears a striking similarity to an envelope previously sent to Berman by Durst.

Both letters were written in block handwriting and the writer misspelled Beverly Hills as "Beverley" on both occasions.

Durst also made headlines in 2003, when he was acquitted in the murder of Morris Black, whose dismembered body was found stuffed in plastic garbage bags in Galveston Bay, Texas, two years earlier. Durst admitted he dismembered Black’s body, but was acquitted after claiming self-defense.

The New York Times reported that more than two years passed before the filmmakers found the audio.

Judge Andrew Napolitano was asked on "Fox Business Network" this morning whether this apparent confession will lead to Durst's conviction in a new trial. 

Napolitano explained that the audio tape represents a "spontaneous admission," not a legal confession and it will be heavily disputed in court.

He said an official confession can only be made to the government when the person receives warnings and states that they fully realize what they're saying.

The judge said there will also be many questions about Durst's mental state that would come up at trial and about whether he knew right from wrong when he said "killed them all."

Napolitano believes it will be difficult for prosecutors to convince a judge not to grant bail to Durst. 

"The government knew for a long time about this garbled statement and chose not to arrest him. Therefore they cannot argue he's a danger. If he's a danger today, he was a danger the day before they arrested him," he said.

Overall, Napolitano doubts that the new audio by itself is going to be enough to convict Durst.

"Prediction? This is not going to move the ball in a positive direction toward the prosecution," said Napolitano. 

Watch his analysis above, and tune in to "Varney & Co." weekdays at 11a ET on FBN to hear much more from the judge.

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