A report on the Columbine High School massacre ... could answer questions about what police knew before the shootings that left 13 victims and two gunmen dead. The families of the victims of the April 20, 1999 massacre were the first to see, in private, [a] mountain of evidence. Some of the evidence is expected to show that Harris and Klebold were on police radar nearly two years before the attack. Brian Rohrbough, whose son, Danny, died at Columbine, said he was hopeful that he would get the answers he and other family members have been seeking. Rohrbough [has] been one of the most vocal critics of the sheriff department's failure to follow up on tips about Harris in the 18 months before Columbine. I have a hard time sleeping at night because I cannot share with you what I know," he said hours before the report was to be released. Rohrbough and some other relatives of victims have seen a deposition given by Wayne Harris, father of Eric Harris. A federal magistrate has ordered the deposition, which is already sealed, destroyed. Rohrbough also is pressing for release of an investigation by the school district, which the district insists it must withhold because teachers questioned during the probe haven't given their permission. Rohrbough is convinced school staff saw a video the teen killers made that gave a hint of their plans. "We were lied to about a number of things and it seems like that things were hidden from us and we never understood why," said Scott. "And I honestly think the answers are not in the things we looked at yesterday. I think they're in sealed reports and possibly things that have been destroyed," he said.