Could a New California Law Bring a New Chapter in Menendez Brothers' Killings?

A new documentary will delve into the infamous case more than 20 years after Lyle and Erik Menendez killed their parents at their Beverly Hills mansion.

Nearly three decades after the wealthy Menendez brothers' crimes captivated the nation, a new documentary is casting a spotlight on their grisly killings once again.

"Snapped: Notorious - The Menendez Brothers," which airs October 2, delves into the infamous case of Lyle and Erik Menendez, who were sentenced to life in prison for the 1989 murders of their parents at their $4 million Beverly Hills mansion.

Read: America's Most Notorious Killers

Now, more than 20 years after their convictions, the documentary suggests a new California law, which concerns the testimony of sexual assault victims, could bring the case to light again.

Erik was just 18 and Lyle was 21 when they gunned down their parents, Jose and Kitty, inside their Beverly Hills mansion on August 20, 1989.

For seven months after the killings, the duo spent their parents' money lavishly. They bought expensive watches and cars, dined at the city's finest restaurants and stayed in posh hotels.

Their spending aroused suspicion of investigators, but it was Erik's full confession to a psychotherapist that ultimately led to their arrests.

When their first trial was broadcast on Court TV in 1993, it became one of the most-watched trials in television history. During the trial, the defense said the brothers killed their parents after years of sexual, emotional and physical abuse.

The jury deadlocked, making way for a retrial.

In the second trial, which was not broadcast, the judge did not permit defense witnesses to argue the brothers had been sexually abused.

Read: Mom Attacked by 2 Sons Begs for Help in Chilling 911 Call: 'My Children Are Trying to Kill Me'

They were convicted of two counts each of first-degree murder and conspiracy to commit murder. In 1996, they were sentenced to life in prison without parole.

The new documentary revisits the brothers' entitled upbringing and family life. It takes another look at the case using original recordings and through interviews with former Beverly Hills Police Captain and murder scene investigator Russ Olson. Friends of the brothers, as well as Erik's former girlfriend, Tracey McEnaney, also give an insight into the killers' minds.

Watch the trailer for the documentary above.

The two-hour special, “Snapped: Notorious - The Menendez Brothers” premieres on Oxygen Media on Sunday, October 2 at 9 p.m. ET/PT.

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