BOULDER, Colo. — The attorney for a school bus driver who was involved in a crash in which the bus overturned said last week in court that she was not impaired at the time, 9 News reports.

Court documents state that Elizabeth Burris was driving erratically before the Dec. 7 crash and her bus, with eight students on board, went off the road, according to the news source. She tried to gain control of the bus, but it went into a spin and rolled over onto its side. Two students were seriously injured, 9 News reports. A state trooper wrote in an arrest affidavit that Burris showed signs of drug impairment and, as previously reported, she said that she was taking about six prescription medications.

Burris has pleaded not guilty to two counts of vehicular assault, eight counts of child abuse, five counts of careless driving resulting in injury, and a charge of driving while under the influence. She is headed to trial in September, according to the news source.

Burris’ attorney told 9 News after a court hearing that she was not impaired by any drugs when she was driving the bus that day, and that that is reflected in a urine screen and a blood test that were completed at the hospital after the crash. The district attorney told the news source that if he determines that the evidence does not support the allegation that Burris was impaired, the DUI charge would be dismissed.

Burris’ employment with the school district ended Feb. 17, according to 9 News. She had been written up 20 times between August 2013 and the time of the crash, including an accident in which she was accused of speeding and tailgating, and numerous instances in which the thoroughness of her pre-trip safety checks were questioned, the news source reports.

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