Los Angeles County District Attorney George Gascón announced his office is reviewing new evidence in the case, which could lead to resentencing. The brothers are currently serving life behind bars for the 1989 killings of their parents in Beverly Hills.
The new evidence includes a handwritten note Erik Menendez wrote to his cousin - before the murders - detailing sexual abuse allegations by his entertainment executive father, Jose Menendez.
"If this was a manslaughter case, instead of a murder case, a manslaughter case - in manslaughter, you get by either imperfect self-defense or heat of passion - if that were the case, they would be out by now and I think that's the argument that they're trying to make," said legal expert Lou Shapiro.
There are two departments within the DA's office that handle these cases: the resentencing unit and murder resentencing unit.
The criteria those units consider include:
- Pre-conviction psychological trauma or physical abuse which contributed to the commission of the offense that was not taken into consideration at the original sentencing.
- Evidence that reflects that circumstances have changed since the original sentencing so that continued incarceration is no longer in the interest of justice.
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How often does resentencing happen?
Since 2021, the resentencing units have reviewed or are currently reviewing 681 cases, according to the DA's office. So far, 300 people have been resentenced and 206 of those people were immediately released from prison as a result.
"The issue is, if this evidence had been presented to the jury in the trial, would it have made a difference in their decision? If that's the case, then it gives merit to reopening," Shapiro said.
Based on the new evidence, the DA's office will present their resentencing decision to the L.A. Superior Court by Nov. 26.
The Menendez case dates back to August 1989, when Lyle Menendez, then 21, and Erik Menendez, then 18, shot and killed their parents, Jose and Kitty Menendez, in the family's Beverly Hills home.
Prosecutors alleged Lyle and Erik Menendez killed their wealthy parents for financial gain, while the defense argued the brothers acted in self-defense after enduring years of sexual abuse by their father.
The brothers' first trials ended in mistrials. In 1996, at the end of a second trial -- in which the judge barred much of the sex abuse evidence -- Lyle and Erik Menendez were convicted of first-degree murder and sentenced to two consecutive life prison terms without the possibility of parole.
In an interview with ABC News, Gascón said he is looking at finding a court date in October to present a separate resentencing decision based on the decades of good behavior the Menendez brothers have exemplified in prison. Regardless, a resentencing decision has to be agreed upon by a judge.
Watch "Menendez Brothers: Monsters or Victims?" from "IMPACT by Nightline," streaming now only on Hulu.
ABC News contributed to this report.
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