Robert Durst back on witness stand at his Los Angeles murder trial

Robert Durst returned to the witness stand Wednesday and gave the judge a thumbs-up when instructed he should limit any “gratuitous” information while testifying at his Los Angeles murder trial.

Before the jury was seated for the day, Judge Mark Windham reminded Durst he was prohibited from mentioning inadmissible topics such as polygraph testing and his mental health during his sometimes long-winded answers.

“I want to make it clear ... I’m instructing you, Mr. Durst, not to mention these subjects,”Windham said.

“I understand,” Durst replied from his wheelchair positioned next to the witness stand inside a courtroom in Inglewood, California.

The standoffish scion of a Manhattan skyscraper fortune started his testimony Monday and immediately proved he remains mentally sharp despite his frail appearance and failed defense motions claiming he was too ill to testify.

In his first words to the jury on Monday, Durst denied killing his friend Susan Berman in December 2000 and made it clear he had no trouble recalling dates, names and addresses while fielding questions from his lead lawyer, Dick DeGuerin.

“Bob, did you kill Susan Berman?” DeGuerin asked as his opening question Monday.

“No,” Durst replied in a hoarse voice.

Durst, 78, is on trial for allegedly murdering Berman inside her Benedict Canyon bungalow on Dec. 23, 2000.

Prosecutors claim Durst shot Berman in the back of her head to guarantee her silence amid a renewed investigation of the unsolved 1982 disappearance of his first wife Kathie Durst in New York.

They allege Durst killed Kathie amid a bitter breakup and then tapped Berman to pose as Kathie and call in sick to his wife’s Bronx-based medical school. The alleged call made it appear Kathie was still alive a day after she disappeared and helped Durst get away with her murder, prosecutors claim.

Kathie’s body has never been found. Durst has not been charged with her murder and claims he has no idea what happened to her.

During his testimony Wednesday, Durst recalled the early years of his relationship with Kathie after they first met at a dinner when she was only a year out of high school, working as an assistant at a dentist’s office.

He said she was only 19 years old when he made her agree as a condition of their courtship that they would never have children.

“I was very, very much against having children,” he said. “I did not want to be a daddy. My childhood had been a disaster. I did not want the same thing to happen to my child.”

Looking back, Durst said it was “totally unrealistic” for him to believe Kathie “giving up everything she always planned for” was an option.

“Clearly Kathie was not going to just accept not having children,” he testified. “Was I making mistake by ruling children out or making a mistake thinking Kathie would be able to live her life and not have children and be happy?” he asked rhetorically.

Kathie’s friends and family have said Durst’s demand that Kathie have an abortion in 1974, a year after their wedding, was a turning point for the couple, fueling the fighting and alleged domestic violence that marked the end stages of their marriage.

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