Last month's fatal Legacy High School bus crash at Denver International Airport may never be officially resolved.
A final police report found no apparent reason that an Adams 12 Five Star Schools bus ran off a road near the airport and into a pillar, killing driver Kari Chopper while injuring 18 students and football coaches.
As reported earlier, Chopper's bus was part of a caravan picking the Legacy team up from DIA on Sunday, Sept. 11. Chopper departed from the terminal with the other buses, then for some reason turned back on a road toward the terminal.
No one aboard the bus could tell police why. There is no indication that Kari Chopper gave any explanation to the two other bus drivers, who followed her back to the terminal, Farr said.
Chopper's husband believes that she made a navigation mistake. An autopsy found that she was not intoxicated or under the influence of drugs. According to her husband, she had never used intoxicants.
Witnesses said the bus was going between 30 and 40 miles per hour when it left the road. There was an on-board computer that may indicate the true speed, but Farr did not have that information at a news conference on Wednesday, Oct. 19. The school district may choose to release the data, he said.
A diagram of the crash shows the bus continued straight as the road turned left, putting it directly into a pillar. Witnesses reported no signs the driver was slumping or unconscious, according to police.
"We simply are going to have to call this one a mystery," said Sgt. Mike Farr of the Denver Police Department.
Josh Chopper told Denverite that his wife may have been trying to stop the bus in order to avoid an upcoming low overpass, and that she may not have been expecting to lose control as the vehicle passed from pavement to dirt. Farr confirmed that the bus was taller than the posted height of the overpass, but he said there still was plenty of time to stop.
"I would be skeptical if that were the case," he added.
An autopsy found that Kari Chopper had an enlarged heart, which indicates she may have experienced a medical emergency prior to the crash. The investigation found no indication that she was suicidal, Farr said.
Two witnesses told officer Mark Miller that the bus moved back and forth across two or three lanes of traffic just before the crash. Sgt. Farr, however, did not report any such detail from witnesses aboard the bus.
Now, the investigator said, it's time to move on. There are no criminal charges to be pursued, he said, and other cases require the department's attention.
"We're closing this one out," he said.
A fundraiser organized by family friends aims to help Chopper's family find a new home; they lost theirs several months before the crash.
