OKLAHOMA CITY (AP) Federal transportation officials said Tuesday that they believe the driver of a semitrailer that crashed into a Texas college softball team's bus last year, killing four players, was likely high on synthetic drugs, although a blood test didn't confirm he had drugs in his system.
During a hearing in Washington, the National Transportation Safety Board voted 4-0 that the likely cause of the September 2014 head-on collision on a highway near Davis, Oklahoma, was the semitrailer driver's incapacitation, ''likely stemming from his use of synthetic cannabinoids.''
The truck driver, Russell Wayne Staley, was charged with four counts of first-degree manslaughter after the collision, which killed four members of the North Central Texas College softball team. A phone number listed for Staley's home in Saginaw, Texas, has been disconnected and his lawyer, Fob Jones, didn't immediately respond to phone and email messages seeking comment.
Authorities found a small pipe containing residue of so-called synthetic marijuana in the truck after the crash. And NTSB investigators said Staley had a history of using synthetic drugs and made no effort to brake or swerve as his truck drifted across a median and into the oncoming bus. But NTSB medical officer Dr. Nick Webster said a blood test couldn't confirm the presence of the drug in Staley's system.
''Testing is extremely difficult and complex,'' Webster said. ''Science does not know how long the substance remains in the blood or what it breaks down to.''
Primarily manufactured overseas, Webster said synthetic cannabinoids stimulate the same brain receptors as the active ingredient in marijuana but are far more unpredictable. The chemicals are typically applied to dried plant material and misleadingly identified as herbal incense or potpourri and sold at gas stations or convenience stores. Users who smoke the product can experience effects ranging from a mild euphoric high to an overdose resulting in psychosis, seizures or even death, he said.
''These chemicals are marketed under hundreds of different enticing brand names, including Spice, K2, and Mellow Mood,'' Webster said. A lab analysis of the pipe residue showed it was a synthetic cannabinoid called 5-fluoro-AMB.
Despite their widespread availability, current Department of Transportation drug testing guidelines don't include testing for synthetic drugs.
''Motor carriers need to know about this emerging class of drugs, and they need better tools to detect driver impairment,'' said NTSB Chairman Christopher Hart.
Killed in the crash were four members of the North Central Texas College softball team: Meagan Richardson of Wylie, Texas; Katelynn Woodlee of Windom, Texas; Jaiden Pelton of Telephone, Texas; and Brooke Deckard of Scurry, Texas.
The team was returning to Gainesville, Texas, from a scrimmage in Bethany when the northbound semi crossed the median on Interstate 35 and struck the left side of the bus.
NTSB investigators determined that none of the bus passengers were wearing seat belts, which contributed to the severity of the injuries, and recommended mandatory seat belt laws for all vehicles.
The NTSB also recommended stricter requirements for medium-sized passenger buses, including stronger roofs, windows and sidewall protections.
A preliminary hearing in Staley's criminal case is scheduled for February in Murray County. District Attorney Craig Ladd did not immediately return a telephone message seeking comment on the case.
National Transportation Safety Board: ntsb.gov
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