The state of Wyoming rested its case Monday in the trial of a truck driver accused of recklessly driving into an ambulance on Interstate-80 near Rawlins three years ago, killing one EMT and seriously injuring another.
The question is not whether Saviol Saint Jean, 46, drove a commercial semitruck and trailer into a parked ambulance and two EMTs walking nearby on the morning of Dec. 21, 2022, as the medics responded to a collision between a commercial truck and enclosed trailer that left both lanes blocked.
That’s been well established in Saint Jean’s trial, which opened Thursday and continues this week.
The question for the jury is whether he behaved “recklessly” enough to commit aggravated vehicular homicide and aggravated assault.
He also faces one count of failing to move away from emergency vehicles.
Saint Jean could face up to 30 years in prison and fines if convicted on all three charges.
Saint Jean’s attorney Joe Hampton on Monday asked Sweetwater County District Court Judge Richard Lavery to acquit him of all three counts, saying the prosecutors didn’t bring enough evidence to trial.
That’s a mid-trial provision Wyoming’s Rules of Criminal Procedure extend to defense attorneys: they can argue to a judge that the prosecutor brought an unsupported slate of charges that the judge should dismiss before having the defense put on his case, if any, and putting the question to a jury.
Lavery denied the motion.

Argument First Though
But first, Hampton waged the claim – after cross-examining two of the state’s expert witnesses at length.
Those were Wyoming Highway Patrol Lt. Tyler Chapman and Western Wyoming Community College commercial driver’s license instructor Sarah Dunn.
“As the court’s aware,” began Hampton, “‘Recklessness’ requires consciously disregarding a substantial and unjustifiable risk that harm will occur, and the harm does occur. In this case there’s insufficient evidence to show Mr. Saint Jean consciously disregarded the risk.”
Chapman, a crash reconstructionist who oversaw the scene that morning, testified “that (Saint Jean) didn’t recognize the hazard and respond appropriately,” Hampton noted.
If the state wanted to bring a charge of criminally negligent homicide (which is a misdemeanor punishable by one year in jail), that would be “fair game,” added Hampton.
Wyoming’s definition of “recklessness” under the aggravated assault charge is even more stringently defined, the attorney noted.
Such a conviction would require the jury to find that Saint Jean acted with “an extreme indifference to human life.”
“There’s no evidence he consciously disregarded the risk of his speed,” said Hampton.
Saint Jean was going about 55 mph in an 80-mph zone that morning. He told an investigator that he though the ambulance lights were on the right — “always on the right” — and he merged into the left lane. He saw people trying to flee, and he tried to stop but it was “too late,” Saint Jean said, according to videos of that interview played at trial.
Chapman said on the witness stand Monday that 55 mph was too fast; that Saint Jean failed to assess the risks, though other drivers on the road that day handled them without crashing.
Chapman also said that the ambulance was parked in the correct spot – a point of contention throughout the trial.
Lastly, argued Hampton, the charge of not moving away from emergency vehicles requires using a safer lane of the roadway, and the legal definitions do not consider the right-hand shoulder part of the “roadway.”
By the time Saint Jean arrived at the crash scene of the overturned trailer and semitruck, the only available lane of travel was the right-hand shoulder. Another trucker pulling doubles, Andrew Gibbs, had fled to the leftward median and gotten stuck in the snow there.
Commonsense
Sweetwater County Attorney Daniel Erramouspe invoked “commonsense” in his spirited counterargument.
“The fact that there wasn’t a roadway is an interesting argument to make, because the only merge that occurred was, the defendant merged into an ambulance,” said Erramouspe. “(Merging) wasn’t even a consideration if you’re driving straight into the thing you’re supposed to avoid.”
As for the two felony charges of aggravated vehicular homicide and aggravated assault, Erramouspe said commonsense should prevail there too.
Dunn had testified that she’d rarely counsel her students to flee onto the road shoulder, because the shoulder may be soft and the truck may roll.
She also testified that commercial truck drivers should slow down if they can’t see 12-15 seconds ahead of their vehicles, since it takes around eight seconds to stop the truck not counting reaction times.
“Yes, she testified you should not drive into a shoulder, and you could roll your semi,” said Erramouspe, adding with sarcasm, “So you run into an ambulance instead?”
“I think Sarah Dunn also said multiple times, if you see emergency lights, you slow down. If you don’t understand what you see in front of you, slow down. If you don’t know where the emergency vehicle is you slow down. He was going too fast to stop,” the prosecutor said.
Because Lavery denied Hampton’s motion, trial continues Tuesday with Hampton’s first witnesses.

Some Background
Before 4 a.m. on Dec. 21, 2022, a red Ford F-150 hauling a trailer jackknifed across Interstate 80 in Sweetwater County near the Carbon County line.
A commercial truck driven by Osvaldo Herrera-Pupo hit the truck and trailer, sending the truck into the left-side median off the road and scattering trailer debris over the interstate, court documents say.
Herrera-Pupo’s truck came to rest in the right lane, leaving both lanes blocked: one with trailer debris, and one with Herrera-Pupo’s truck.
A double-trailer combo driven by Utah-based trucker Andrew Gibbs maneuvered around the crash onto the left side, where it got stuck.
Other cars passed on the right shoulder, according to court testimony.
Tiffany Gruetzmacher drove an ambulance to the scene with her fellow EMT Tyeler Harris in the passenger seat.
She parked west of the trailer debris, mostly or entirely within the left lane, according to court testimony.
Then Saint Jean sped into the scene and into Gruetzmacher and Harris, killing Harris and leaving Gruetzmacher with back, skull, neck and hand fractures, court documents say.
The semi also hit the ambulance.
Hampton’s case has hinged on emphases of how chaotic the scene was, questions about whether the ambulance was parked in the correct place, and indications that the road may have been slick.
Erramouspe and his deputy attorney TahNee Alton, conversely, have emphasized commonsense measures of crash avoidance, how well other drivers performed on scene, and testimony that the road under Saint Jean was dry, not icy, that morning.
Saint Jean, who is Haitian, has an English-language interpreter in trial.
Herrera-Pupo required English translation from his co-driver Brian Perez while trucking, the latter testified Thursday.
U.S. Immigration and Customs Enforcement did not grant a request for their citizenship statuses by publication time Monday.
How High?
Hampton has asked every witness who was at the crash scene that morning how high the enclosed trailer wreckage blocking the left lane was.
The ambulance was parked westward of that wreckage.
The defense attorney’s follow-up questions characterize the original question for the spectator: as an attempt to see whether the ambulance’s lights were blocked or muted by the wreckage.
In a video Erramouspe showed from the dash of a trooper who responded later after the ambulance collision the lights are clearly visible.
Hampton also asked Monday, while questioning Chapman, whether the white lights mixed in with the red and blue could have washed out other relevant lights, such as the hazards on Herrera-Pupo’s truck.
“You testified they’re very bright. Ms. Gruetzmacher testified they’re ‘pretty blinding,’” said Hampton.
“Absolutely,” the lights could have washed out other relevant lights, said Chapman — but only “at a long distance.” Drawing closer would have revealed the other hazards, he said.
Chapman had testified, however, that the pedestrians who were standing on the left median were not standing in a good spot for the circumstances. Hampton has emphasized indicators that the pedestrians complicated Saint Jean's already troubled perception of the scene as he approached.
Shoulds, Should Nots
Dunn had testified that in a wreck, commercial truck drivers must put out triangle advance warnings within 10 minutes, unless they’re too injured to do so.
If the wreck is on an interstate, those signs must be placed at intervals of 10 feet, 100 feet, and 200 feet behind the trailer, said Dunn.
“That’s required by law?” asked Hampton.
“Yes it is,” answered Dunn.
Alton followed up with her own questions.
“If a driver were to see a glare or white spot, what should that driver do?” she asked.
“Slow down,” answered Dunn.
“If a driver perceives road conditions as icy or wet, whether they are or not, what should they do?” asked the prosecutor.
“Slow down immediately.”
Alton asked similar questions about seeing objects and not perceiving what they are, and she received identical answers from Dunn.
Alton asked why commercial truck driving students must learn at least 30 federally approved theories of safety that Dunn teaches.
“So that they understand how dangerous these vehicles are to the general public,” answered Dunn. “They need to understand how fast we’re going, and how much we weigh, and how long it takes for us to recognize a hazard and then either slow down or stop to avoid that hazard.”
Clair McFarland can be reached at clair@cowboystatedaily.com.