The discrepancy is significant for several reasons. The official timeline for the attack, though repeatedly challenged by some victims' families and contradicted by evidence found in 911 calls and dispatch traffic, has been relied on as gospel by numerous journalists, authors and violence-prevention experts seeking to extract the "lessons" of Columbine. The video analysis, if correct, indicates that basic assumptions behind many of those accounts and studies are wrong. It also suggests that the killers' propane bombs, concealed in large duffel bags, sat undetected under tables for much longer than previously believed, while the cafeteria filled with students grabbing lunch.
The full video, released on YouTube by the Crime Video Archives (previously known as the Columbine Video Archives), shows a figure dressed similar to Eric Harris hauling bags into the cafeteria at 10:58 a.m., headed toward the tables where the bombs (which failed to explode) were later found. The closed-circuit camera system, which switches among four different camera angles every few seconds, catches the same individual leaving empty-handed. A few seconds after that, the same angle shows a taller individual, whose long, loping stride closely resembles that of Dylan Klebold, carrying another heavy bag into the Columbine "commons."
The official timeline prepared by the Jefferson County Sheriff's Office states that Harris and Klebold brought the bags into the cafeteria at 11:14 a.m. The event supposedly wasn't captured on video because, by an unfortunate coincidence, a custodian was in the process of changing tapes for the surveillance equipment at the time. But that timing always seemed strange to some observers, cutting things a bit close, since the "plan" had called for the bombs to explode at 11:17 a.m., and the pair had to get back to their cars to set car bombs as well.
JCSO spokesman Mark Techmeyer declined to comment on the video. "This is a closed investigation, and we no longer have anything of evidentiary value to evaluate," he said.
The Columbine investigation involved many months of police work by representatives of more than a dozen law enforcement agencies and included extensive review of the surveillance footage from the cafeteria. But if the investigation somehow missed the arrival of the killers with their bombs, it wouldn't be the only error in the official timeline.
Faced with lawsuits and widespread criticism of the police response to the attack, investigators were under some pressure to present findings in a light favorable to law enforcement. A Westword analysis of 911 and dispatch calls, released many months after the attack, showed that the sheriff's report incorrectly claimed that officers were on scene earlier than they actually arrived. One gun battle between Harris and officers on the school's west side apparently occurred more than ten minutes later than the report claims it did. And, of course, officials worked earnestly for two years to conceal a draft affidavit for a warrant to search Eric Harris's house, prepared a year before the attack in response to complaints that he was building pipe bombs and threatening other students.
Here's the complete video analysis posted on the Crime Video Archives channel.