Nyabuto trial day 8: Defense toxicology expert questions level of intoxication claimed by state

TYLER, Texas (KLTV) - The eighth day of the trial for a Grand Prairie man accused in the traffic death of a Smith County sheriff’s deputy began with the continued testimony of a toxicology expert.

Daniel Nyabuto, 22, is charged with intoxication manslaughter in the 2022 death of Deputy Lorenzo Bustos, who was in the final stages of his training with the Smith County Sheriff’s Office.

The defense continued to question their witness, forensic toxicology expert Dr. Jimmie Valentine, on the validity of the state’s claims about Nyabuto’s mental state on the night of the crash. Valentine is a lifelong academic in the field and has taught at several universities. On Thursday, Valentine said he had concerns over the results of Nyabuto’s BAC test, and cited the way Texas DPS conducts their testing.

To begin Friday’s proceedings, Valentine and the defense discussed the bodycam footage of trooper Kody Gayle, who conducted a sobriety test on Nyabuto the night of the crash. Based on the footage, Valentine said he did not see any behavior consistent with the .144 BAC claimed by DPS. He also called into question the standardized sobriety test used to determine probable cause, saying it can be affected by physical factors like the firing of an airbag.

The state began to cross-examine Valentine, pointing out that the defense did not play the walk-and-turn portion of the bodycam footage in which Nyabuto appears to be off-balance. They asked Valentine if the defense could conduct their own test of the unopened blood vial offered into evidence, and Valentine said it was possible.

The defense then called their own crash reconstruction expert, Dusty Harrington with Adams Engineering. He disagreed with DPS’s crash reconstruction video, where Sgt. Chad Martin drove approximately 65 mph on Hwy 155 and avoided a parked Tahoe. He testified that the reconstruction is not an accurate representation of what Nyabuto would have seen on the night of the crash, and rather than a visibility distance of 600-700 feet, he said that Nyabuto would have been able to see the vehicle from 570 feet away.

Harrington said that Nyabuto reacted how a normal driver would in the situation, and that data from Nyabuto’s airbag control module showed that he applied the brakes before the crash, saying “He sees something, he sees it’s a hazard, but he’s not sure how to react.”

The court went to recess for lunch, and will return with Harrington’s continued testimony.

3 p.m. update:

In cross-examination, Harrington said that Nyabuto’s steering wheel had “input to the left” seconds before the crash. The state showed pictures from the scene depicting damage to the front driver’s side of Nyabuto’s car and the rear passenger side of Bustos’ Tahoe. More photos showed Nyabuto’s car at rest close to the curb after the crash. The then showed Bustos’ bodycam footage again, pointing out that the noise of screeching brakes are only heard just before the impact. Harrington said that was to be expected.

Harrington finished his stay at the stand by saying that Nyabuto’s actions were consistent with that of an average and confused driver, but not an intoxicated one.

The defense rested at 2:58 p.m., and the state began to recall witnesses.

4 p.m. update:

Martin was brought back to the stand by the state. Martin expressed his disagreement with Harrington, saying he does not believe Nyabuto was attempting to change lanes. Martin said his own analysis did not show Nyabuto attempting to pull the steering wheel left before the impact. Martin said he calculated that a sober person would need 339.4 feet traveling at 65 mph to come to a complete stop. He pointed out that Harrington calculated that Nyabuto would have been able to see Bustos’ vehicle from 570 feet away.

Both the state and defense have rested in the case of Nyabuto. Due to the coming holidays, Judge Kerry L. Russell ordered jurors to return on Jan. 9 for closing arguments, citing law that jurors must be kept together once they deliberate.

Related:

• Deputy struck, killed by drunken driver on final night of field training, sheriff’s office says
• Judge grants delay in trial of man accused in Smith County deputy’s death
• Grand jury indicts man accused in death of Smith County deputy on 2nd charge
• Lawyers request suppression of evidence against man accused in death of Smith County deputy
• Trial begins for Grand Prairie man accused in traffic death of Smith County deputy
• Nyabuto trial day 2: Smith County deputy on scene of fatal crash discusses bodycam footage
• Nyabuto trial day 3: Trooper who conducted sobriety test describes ‘strong odor of alcohol’
• Nyabuto trial day 4: Defense questions procedure of trooper who performed sobriety test
• Nyabuto trial day 5: bar, restaurant managers questioned about Nyabuto’s drinking
• Nyabuto trial day 6: DPS officer describes recreating fatal crash scene
• Nyabuto trial day 7: Medical examiner describes conducting autopsy on Deputy Bustos