Victims' families and their attorneys cheered the release as a major victory. "I am expecting to gain a lot of information from this report," says Brian Rohrbough, whose son Dan was killed in the attack. "Part of what I'm expecting to learn ... is what's missing from this report."

The material released Tuesday filled four large storage boxes. County spokesman John Masson says it amounts to a "substantial" portion of the data available. But it omits a great deal of crucial evidence -- including autopsy reports, thousands of photos and medical reports of the victims -- that could be useful in lawsuits that have been brought on by families of Columbine victims.

Among the most compelling documents are 16 pages of testimony from Patty Nielson -- the teacher famous for making 911 calls from the library as the killers rampaged through the building -- that effectively refute the most misleading myth of all: that the entire tragedy was intended as a horrible attack on jocks, blacks and Christians.

The testimony substantiates an argument investigators have been trying to make since September 1999: The massacre at Columbine was random and indiscriminate -- it wasn't based on targeted groups or a hit list. (Though several so-called hit lists did exist, they don't appear to have played any role in the final killings.) Material leaked from Eric Harris' diary and the so-called "Suicide Videos" supported that conclusion, but it arrived months after the conception of the attack was firmly planted in the public perception. And for several days after the massacre, the media drove home the message that it was directed against jocks and blacks, with relentless attention to the now infamous line "All jocks stand up." Until now, investigators have refused to release significant testimony from the attack to effectively dislodge that misperception.

Nielson repeatedly describes killers Harris and Klebold moving methodically through the library, pausing to torment their victims before shooting them, seemingly indiscriminately.

"It was her belief that the suspects were going around and shooting every student who was hiding underneath the tables," the interview report states.

At one point in the testimony, Nielson recalls one of the killers yelling "Kill all the jocks." At one another, she hears one say: "What do we have here, a nigger?" -- presumably before the murder of Isaiah Shoels.

"Patty Nielson stated it was clear in her mind the suspects were attempting to humiliate the victims prior to shooting them," the document says.

She says the killers repeated their demand that everyone "get up" several times, and describes them heckling any number of students, for the most trivial reasons. She says one killer asked, "Whatta we got her, a fat boy?" His partner responded that he could "do whatever you want with that one, I don't care." Another student was taunted for his glasses: "You think those glasses look cool[?]"

Because Nielson remained hidden beneath the library's front counter as most of the shootings occurred, she was often unable to ascertain which killer said what.

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