Columbine killers thank gun providers on video

Manes' sentencing hearing finally forced tight-lipped authorities to begin revealing fragments of interesting data about how Harris and Klebold planned and executed the attack, in advance of the highly anticipated final report on the massacre, expected to be completed in the next few months.

At the hearing, Battan disclosed details about the twin suicides, the number of victims killed by each shooter, and how they trained for the attack. Her testimony should close the lid on persistent rumors that Klebold was merely a follower of Harris, considered the leader and mastermind of the attack.

Investigators have denied this characterization for months, labeling them equal killers, but Battan finally revealed detailed evidence to support their contention Friday. Klebold, for instance, was the one who fired the TEC-9 55 times during the rampage, killing four and injuring two with that weapon alone.

Harris killed an equal number and injured seven more with a pump shotgun, firing just 25 times. That still leaves seven deaths unaccounted for, because each killer carried a second weapon unrelated to Manes' sentencing. Investigators only revealed data specifically related to this case.

But other sources inside the investigation have confirmed for Salon News that the killings were nearly evenly split between Harris and Klebold. Various rumors have also persisted about the killers' own deaths, including questions of whether one might have killed the other. But for the first time, Battan cited forensics evidence which confirms that Harris and Klebold each killed themselves with their own gun.

Both prosecution and defense tried to use the videotape to their advantage. "The only people the killers thanked for helping them were Mark Manes and Phil Duran," the prosecutor said. He then quoted the video: "'You helped us do what we needed to do.'"

Battan confirmed that in the mountain of writings, videotapes and personal testimony complied on the killers, the only other person they thanked was a man behind the corporation that manufactured one of the shotguns.

But the defense argued vehemently that Manes was completely oblivious to what the gun would be used for. Battan agreed that she'd uncovered no evidence to indicate otherwise.

Nine family members testified about the impact of the tragedy on their lives, repeatedly urging Judge Henry Nieto to send a message that gun laws would be enforced. Jensen echoed that message, calling Columbine "the worst case example of what can happen when this law is violated." He urged the judge to base the punishment on the harm caused by the sale, to convince gun sellers that "You will lose big time" if someone is later killed or injured by that gun.

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