A trash truck driver who had marijuana in his system likely caused a fatal collision last year with an Amtrak train that was carrying Republican lawmakers, federal investigators concluded Thursday.
The National Transportation Safety Board's final report said the crash in rural Virginia was likely caused by the truck driver's decision to go around a rail crossing's lowered safety gates. The agency also cited the driver's "inaction" while stopped on the tracks.
Drugs likely played a role as well, the NTSB said. The driver's blood contained the psychoactive ingredient in marijuana as well as an anti-seizure medication for which investigators found no prescription.
The ensuing collision killed a passenger in the trash truck and severely injured another. Several people on the train were hurt, including a congressman who suffered a concussion.
The train was carrying Congress members to a strategy retreat at the Greenbrier resort in White Sulphur Springs, West Virginia. The crash occurred in Crozet, just outside of Charlottesville.
The report said marijuana impairment is evident through slower decision-making and noted the driver's "indecision when he encountered obstacles while trying to cross the tracks."
"The truck driver's lack of response after stopping the truck and being positioned between two obstacles for several seconds is an example of slow decision-making," the report said.
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The trash truck's driver, Dana William Naylor Jr., had already been indicted locally on involuntary manslaughter and DUI charges.
But a charge of maiming under the influence was dropped after a judge ruled out certain scientific testimony and blood evidence, the Daily Progress reported.
Last month, a jury found Naylor not guilty of involuntary manslaughter. He still faces civil suits filed by people who were on the train.
William Tanner, Naylor's attorney during the criminal trial, did not immediately respond to a phone call from The Associated Press seeking comment on the NTSB's report.
The NTSB's findings may have little impact on Naylor.
NTSB spokesman Keith Holloway wrote in an email that the agency "does not have any enforcement authority" and that "there is no legal action that can be taken by the board."
Former Minnesota Republican Congressman Jason Lewis was in one of the train's passenger cars and suffered a concussion after his head struck a seat.
"There but for the grace of God it could have been a lot worse for some of us on the train," Lewis, 63, said on Thursday.
Lewis said the crash raises concerns about driving under the influence of marijuana at a time when the drug is being legalized in more states across the U.S.
"We have to find a way to prevent this sort of thing," said Lewis, who lives in Woodbury, Minnesota, outside St. Paul.
"Most people don't want to go back to prohibition, but they're certainly opposed to drunk driving," he said. "You can be the most ardent advocate for decriminalizing marijuana, but nobody I know would want somebody who is high on the job."