Lyle Menendez Explains Notorious 911 Call Following Parents' Murder

For the first time in nearly two decades, Lyle Menendez is speaking out about the 911 call he made after murdering his parents, saying that he wasn't "grief-stricken" at all.

"I think I was just absolutely broken down with stress," he tells NBC News' Keith Morrison in an exclusive clip from Friday's Dateline, which re-examines the Menendez brothers case. "Both of us were just in such a state of trauma and I just — it didn't pour through on that call," he says. "It made it very easy to make that call, really."

In 1994, Lyle and Erik Menendez were found guilty of murdering their parents on the night of Aug. 20, 1989. The investigation showed that the brothers, then 21 and 18, armed themselves with 12-guage shotguns and burst into the family den where their parents were watching TV. José Menendez was shot at point-blank range and Mary "Kitty" Menendez was shot as she attempted to flee. By the time the shooting was over, they had been shot more than a dozen times.

The brothers became suspects in the case after they began spending the family's fortune, with prosecutor's saying that the slayings were a scheme to get their parents' $14 million estate. But throughout the course of the trial, both Menendez brothers claimed that they had committed the murders after years of abuse at the hands of their parents.

The two were convicted of first-degree murder in 1996 and sentenced to life in prison without the possibility of parole. Lyle Menendez claims that their crimes were distorted by authorities.

"There are, like, 200 to 300 hundred parricide cases a year, where a parent is killed by a child. And they are almost all related to abuse. And they are almost all settled," Menendez says during the interview according to PEOPLE. "This case they picked out as different. And I think that it was very easy, because it was Beverly Hills and my father had a lot of money, to sort of sell this headline that these brothers killed for money."

Dateline's Unthinkable: The Menendez Murders airs Friday at 9 p.m. ET on NBC.