(ABC News) -- A grand jury believed there was enough evidence in 1999 to indict John and Patsy Ramsey on charges relating to the still-unsolved killing of their beauty queen daughter JonBenet Ramsey, ABC News sources say.
Six-year-old JonBenet was found dead in the basement of her family's upscale Boulder, Colo., home Christmas Day 1996. Suspicion fell on her parents, John and Patsy Ramsey, but they insisted an intruder was to blame and they were never prosecuted.
In an interview with ABC News' Barbara Walters after her death, both of the girl's parents denied that they had killed her. They were eventually cleared by prosecutors.
After meeting for more than a year, a grand jury found sufficient evidence to indict the couple on charges of child abuse resulting in death, as first reported Sunday by the Boulder Daily Camera and confirmed by two separate sources by ABC News.
"This grand jury, in effect, came up with a compromise finding, 'No, it's not murder,' but, 'Yes, we think they were responsible' for the death based on abuse," ABC News legal analyst Dan Abrams said.
But District Attorney Alex Hunter refused to sign off on the grand jury's decision, saying there was too little proof.
"I and my prosecution task force believe we do not have sufficient evidence to warrant the filing of charges against anyone who has been investigated at this time," Hunter said then.
Hunter believed a conviction would be impossible. Abrams said that he agrees with the decision.
"I've seen the majority of the case files and I think Alex Hunter made the right call," he said. "I think there simply was not enough evidence to move forward."
Patsy Ramsey died in 2006 after a battle with ovarian cancer. John Ramsey remarried. His attorney told ABC News that Hunter is "a hero who wisely avoided a miscarriage of justice."
The case is still officially open but, as in 1996, investigators seem no closer to solving the crime this year, when JonBenet would have turned 23.
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