Here are the Menendez brothers' potential tracks to freedom

Lyle and Erik Menendez are currently serving life behind bars for the murders of their parents in the family's Beverly Hills home. But after more than three decades in prison, a renewed interest in the headline-grabbing trial has the brothers pursuing two tracks to potential freedom.

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.

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.

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Their first trials -- which captured the nation's attention with cameras in the courtroom -- 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.

The sensational case gained new attention this fall with the release of the Netflix drama "Monsters: The Lyle and Erik Menendez Story" and the Netflix documentary "The Menendez Brothers."

The brothers currently have two potential paths to their release before the Los Angeles County District Attorney's Office.

Resentencing

One track involves a review of their sentence based on factors including rehabilitation, which Los Angeles County District Attorney George Gascón is evaluating.

Gascón said he plans to make his resentencing decision this month. If Gascón recommends resentencing, his recommendation will go to a judge to decide whether the brothers will be released, receive a lesser sentence or get a new trial.

Gascón told ABC News in October any recommendation for resentencing would take into account the decades the brothers already served and their behavior in prison.

Mark Geragos, the Menendez brothers' lawyer, called Erik and Lyle model prisoners who worked tirelessly to reform themselves with no expectation they'd be released.

"Given the totality of the circumstances, I don't think that they deserve to be in prison until they die," Gascón told ABC News.

Gascón said since he's been in office, they have resentenced over 300 people, of which four have reoffended.

New evidence

The other track concerns the brothers' petition filed last year for a review of new evidence not presented at the original trial. Through the habeas corpus petition, the court could reverse the conviction or reopen proceedings.

Gascón said his office is evaluating allegations from a member of the boy band Menudo who said he was molested by Jose Menendez, and a letter Erik Menendez wrote to a cousin eight months before the murders detailing his alleged abuse.

Erik Menendez's cousin testified about the alleged abuse at trial, but Erik Menendez's letter -- which would have corroborated the cousin's testimony -- wasn't unearthed until several years ago, according to Geragos.

"The combination of those two we believe provide more than ample basis to set aside the result of the second trial," Geragos said at a press briefing earlier this month.

Geragos said the district attorney could either oppose the habeas and decide to litigate it, or "they could concede the habeas and say, give them a new trial."

"I'm hoping that sometime before Thanksgiving, which is when the next response is due, that the DA will either concede the habeas or join us in asking for resentencing," Geragos said.

The next court date in the case is scheduled for Nov. 26, Gascón said.

Family calls for release

Nearly two dozen relatives have urged the district attorney to recommend the brothers be resentenced and released.

Lyle and Erik Menendez "were failed by the very people who should have protected them -- by their parents, by the system, by society at large," Kitty Menendez's sister, Joan Andersen VanderMolen, said at a news conference on Wednesday.

"Their actions, while tragic, were the desperate response of two boys trying to survive the unspeakable cruelty of their father," she said of the murders. "As their aunt, I had no idea of the extent of the abuse they suffered."

Behind bars, the siblings "persevered," Anamaria Baralt, niece of Jose Menendez, said. "They have sought to better themselves and serve as a support and inspiration for survivors all over the world. Their continued incarceration serves no rehabilitative purpose."