( CNN ) -- The former lead investigator in the JonBenet Ramsey case says that newly released documents may spark renewed interest , but they have little effect on the cold case investigation . Previously sealed court documents released Friday show that a Colorado grand jury voted in 1999 to indict the parents of the slain 6-year-old JonBenet on charges of child abuse resulting in death and being accessories to a crime . Court papers : Grand jury in 1999 sought to indict JonBenet Ramsey 's parents . The district attorney decided that year , however , not to file charges against John and Patricia Ramsey , saying there was insufficient evidence . In 2008 , a new district attorney said new DNA evidence cleared the parents and their son in the death . The case has never been solved , and the released documents have put the killing back in the spotlight . But attention does not necessarily translate into leads in the case , former lead investigator A. James Kolar told CNN . `` It is unlikely unless there is a confession , or somebody else comes forward that has information that has been shared with them , '' he said . Read the documents . Kolar wrote a book about JonBenet 's killing and said he does not believe that there was an intruder at the Ramsey house that night , implying that the Ramsey family -- the late Patricia Ramsey , her husband John and their son Burke -- know more than they have told . What exactly was it that kept the district attorney from pursuing the charges ? `` That 's a very complicated question . I think there are a lot of things that could be considered missing from the D.A . 's perspective to be able to bring them to a threshold of prosecuting beyond a reasonable doubt , '' Kolar said . Still , the documents released Friday are an important part of the history of the case . A Colorado court ordered the release of the previously sealed court documents about the unsolved 1996 death of the girl who won child beauty pageants and whose murder shocked the nation . The pages were sealed in 1999 , after the grand jury in the case dispersed without charges being filed .
New documents in the JonBenet Ramsey case were released Friday . The Boulder County District Attorney's Office said it will not seek a new trial for John and Patsy Ramsey, who have been charged with murder after their 6-year-old daughter was found dead on Christmas Day 1996. But the renewed attention does not mean new leads , he says .