Prosecutors said Berman had helped him provide a false alibi in connection with his wife Kathleen McCormack’s disappearance in 1982.
It was alleged that he killed Berman to prevent her from revealing this to the police.
Durst, a wheelchair-bound cancer survivor, spent 15 days testifying during the trial, claiming he had found his friend’s body when he went to visit her.
While Durst, believed to be worth $ 100 million, was only on trial for killing Berman, prosecutors believe he murdered two others – his wife and a neighbor in Texas who discovered his identity while hiding from police.
Durst has never been charged with the disappearance of McCormack, who was a 29-year-old medical student when she disappeared.
He has long been a suspect and Westchester County District Attorney Mimi Rocah reopened the case in May.
As for the murder and break-up of the Texas neighbor, Morris Black in 2001, Durst was tried but acquitted.
He had claimed that Black was shot by mistake when the two men were fighting for a gun.
The trial of Berman’s murder – which began in March last year but was suspended for 14 months due to the coronavirus pandemic – came six years after an HBO TV series The Jinx.
Durst was still wearing a live microphone after his interview in the series and was heard saying to himself in the bathroom: “What the hell was I doing? … killed them all, of course”.
Chief Prosecutor John Lewin said the interviews in the series had helped bring charges against Durst.
Durst is the grandson of Joseph Durst, who founded the Durst Organization, one of Manhattan’s largest commercial real estate companies.
His father, Seymour, took control of the company and later gave it to a younger brother, Douglas.