Hearings that could result in the Menendez brothers being re-sentenced or released will be allowed to go ahead this week, after a judge knocked back prosecutors' attempts to scuttle them.
Los Angeles County District Attorney (DA) Nathan Hochman confirmed the court would proceed with a re-sentencing hearing for the brothers on April 17 and 18, saying the re-sentencing hearing was "unexpected".
Lyle and Erik Menendez, now 57 and 54 years old, were convicted in 1996 of first-degree murder and sentenced to life in prison without the possibility of parole for killing their parents, Jose and Kitty Menendez, at their luxury Beverly Hills home in 1989.
Mr Hochman had opposed re-sentencing, which could make the brothers eligible for parole and possibly result in their release after 35 years behind bars, with filing a petition to withdraw a request for re-sentencing in March.
This week, he said the pair should remain behind bars because they had never accepted their guilt and continued to rely on untruths.
“These murders were calculated, premeditated, cold-blooded killings," Mr Hochman said.
"Our position remains clear: Until the Menendez brothers finally come clean with all their lies of self-defence and suborning and attempting to suborn perjury, they are not rehabilitated and pose an unreasonable risk of danger to public safety.”
He also criticised that the former prosecutor did not "examine or consider whether the Menendez brothers have exhibited full insight and taken complete responsibility for their crimes".
"A full examination of the record reveals the Menendez brothers have never come clean over the past three decades and admitted that they lied about their self-defence, as well as suborned perjury and attempted to suborn perjury by their friends," he added.
Mr Hochman's predecessor, George Gascon, had favoured the release of the brothers based on evidence that recently emerged suggesting they may have been abused by their parents.
Appalling crime in 90s
The case captivated the US in the 1990s because of the duo's wealth and privilege as sons of a record company and entertainment industry executive.
The brothers were arrested in 1990 and soon admitted to the killings but insisted they acted in self-defence after years of sexual, emotional, and physical abuse.
Lyle was 21 and Erik was 18 years old at the time of the murders.
A recent Netflix documentary series raised new evidence to support their claims they were sexually abused by their parents, which led Mr Gascon to advocate for a re-sentencing hearing, according to Reuters.
The pair, at first, denied involvement and attempted to point the finger of blame at the mafia to make the shooting look like an organised crime.
Some members of the Menendez family, including Jose and Kitty Menendez's sisters, have supported the brothers' release.
However, Milton Anderson, who was the brother of Kitty Menendez and died recently, repeatedly opposed their release and disputed the abuse claims.
ABC/wires