A new trial for Lyle and Erik Menendez, after 35 years in prison for the shotgun murder of their parents, has been turned down by the Los Angeles County District Attorney.
However, Nathan Hochman said a decision had not been made on a resentencing bid that could lead to their release.
The brothers were found guilty in the 1989 murders of their entertainment executive father, Jose, and their mother, Kitty Menendez, and sentenced to life in prison without parole.
Their latest bid for freedom focuses on new evidence of their father's sexual abuse.
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However, Mr Hochman cast doubt on the evidence and said it was not pertinent to the case.
"Sexual abuse in this situation may have been a motivation for Erik and Lyle to do what they did, but it does not constitute self-defence."
He also said the brothers' own testimony of sexual abuse was untrustworthy because they had told five different explanations for why they committed the murder.
The Menendez family called the decision "abhorrent" and said he "discredited the trauma" experienced by the brothers.
"Abuse does not exist in a vacuum. It leaves lasting scars, rewires the brain, and traps victims in cycles of fear and trauma," they said in a statement.
"To say it played no role in Erik and Lyle's action is to ignore decades of psychological research and basic human understanding."
The family said new evidence should not be needed, as the justice system failed the brothers back then and "continues to fail them now".
Lyle and Erik Menendez admitted they killed their parents with a shotgun, but said they feared they were about to kill them due to details of their father's long-term molestation of Erik being made public.
Prosecutors said at the time there was no evidence of molestation, and many details in the brothers' story of sexual abuse were not permitted in the trial that led to their conviction in 1996.
Prosecutors accused the brothers of killing their parents for money.
The proposed resentencing for the brothers is still set to be taken up at a March hearing and would make them immediately eligible for parole.
The Menendez case was thrust back into the limelight after Monsters, a Netflix drama telling of their story, and a documentary were recently released.
(c) Sky News 2025: New Menendez trial rejected - but resentencing bid could see brothers walk free
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