The husband and wife sat on the hill overlooking the dirt parking lot, watching cars crunch up the unpaved road into Red Butte Canyon.

Authorities say they had already killed one man back in Colorado and were both wearing the dead man’s clothes against the Utah chill. Now they wanted to get to Tennessee.

Austin and Kathleen Boutain decided they would kidnap someone, a random driver in the hills covered with fields of high grass cowlicked by the mountain wind just east of the University of Utah in Salt Lake City, according to documents presented Thursday by the District Attorney for Salt Lake County along with an indictment of the pair. The driver’s credit cards and money would pay for food and fuel, the couple later admitted to police.

They planned to kill their victim in the Utah canyon or take him along and kill him in Tennessee — the couple had not figured that piece out yet, they told police.

So the Boutains eyed the cars, waiting for the right one. But as the afternoon beat on, Kathleen’s patience frayed. Every time she pointed a vehicle out to her husband, Austin hesitated. Another vehicle would come up. Don’t want witnesses, he’d say. Or it was too light out still. Excuses. He was taking too long to find a victim. Finally she told Austin he was a coward. The 24-year-old pulled out the .44-caliber Ruger handgun and pistol-whipped his wife for questioning his resolve to kill, the couple told police. Kathleen broke away and ran off down the dirt road out of the canyon. She passed a black car pulling up into the parking lot.

When his wife did not return, Austin walked down the hill to gravel lot. As he would later explain to police, he knocked on the car’s window to see whether the driver knew which way Kathleen had gone. He knocked again when no one answered, his temper flaring. He started yelling as the car drove away, then wrenched the Ruger free, firing into the driver’s side window until the gun clicked empty, he told police.

The Oct. 30 shooting in Salt Lake City was the last act authorities attribute to the Boutains, a tattoo-splattered couple who took a crash course through the western United States. Although the random killing made headlines across the nation, only this week have investigators released court documents describing what they say is the drifter couple’s violent run, including a murder attempt with a crossbow, an actual murder with a knife, and bizarre plans for cross-country kidnap plot. Now both face murder charges in Utah and are likely to be indicted in Colorado as well. They have not yet entered a plea, nor were there attorneys listed for them as of Thursday, according to the Associated Press.

Kathleen (left and Austin Boutain face charges in two murders.)

Little public information throws light on either of the Boutains’ backgrounds. In his mug shot, Austin has large flowers and Gothic script scrawled across his neck, tattoos dripping from his eyes, and more undecipherable wording printed above his right eyebrow. Police records indicate he has previous felony convictions, including a charge in Alabama of failing to register as a sex offender and a conviction for theft of a motor vehicle. He was on probation at the time of the Utah and Colorado killings. The AP reported that he was in prison until spring, and that he skipped parole in Wisconsin.

Recent police records indicate that in late October the couple was living in a tent under a bridge in Golden, Colo. There they met Mitchell Ingle, a “friend to all” in the words of his family who enjoyed skiing and other outdoor activities. The 63-year-old lived in the Clear Creek RV Park, and Austin had previously sold Ingle marijuana, according to the Salt Lake Tribune.

On Oct. 27, the Boutains visited Ingle with marijuana and a bottle of cinnamon whiskey. The three drank and smoked, but Austin became enraged when the older man made sexual comments about Kathleen. When Ingle went to sleep, the couple decided to kill him, they told police.

Austin originally tried to shoot the sleeping Ingle with a crossbow bolt, authorities say. The arrow missed, but woke Ingle. Unaware of what was going on, the older man went to the bathroom. Austin followed him inside the RV’s bathroom, where he allegedly cut Ingle’s throat with the knife, the Tribune reported.

The couple first thought about stealing Ingle’s trailer, police records say, then thought better — it was too bloody. Instead, they ransacked the RV, taking money, prescription drugs, a .308-caliber Winchester rifle, a .44-caliber Ruger handgun, a .38-caliber Smith & Wesson handgun, ammunition, three knives, blankets, clothes and Ingle’s green F350 Ford truck, police records say.

While Ingle’s body lay undiscovered in the trailer, the couple traveled in the stolen truck to Salt Lake City. On the road, they picked up another couple at a truck stop. In Salt Lake City, the Boutains gave the truck away to the couple so that they would not have to dispose of it, police records indicate.

The Boutains set up a camp in Red Butte Canyon, eventually coming up with their plan to kidnap an unsuspecting driver for passage to Tennessee.

ChenWei Guo was the student killed in an attempted carjacking near campus on Oct. 30. (University of Utah/AP)

On Oct. 30, as Kathleen ran from her husband down the road leading into the canyon, ChenWei Guo, 23, pulled his car up into the park.

An international student from China, he was a computer science major at the nearby University of Utah, where Guo also worked as a peer adviser in the International Student and Scholar Services Office. Deeply committed to his Mormon faith, he had previously served a Church of Jesus Christ of Latter-day Saints mission in Provo. Xiaoying Ding was in the passenger seat of Guo’s car when Austin started banging on the window in the gravel lot.

Guo attempted to pull the car away as bullets came crashing through the window, Ding would later tell police. Guo was hit in the neck, and the car slammed into a rock on the berm. He died of the gunshot wound, according to the AP. Ding climbed into Guo’s lap to get control of the car, but she didn’t know how to drive. She called 911 at 8:38 p.m.

While she spoke with the operator, Austin stood outside the vehicle, listening to the woman’s voice, deciding what to do. He paced the hillside and then, as he recounted to police, returned to the vehicle after a few moments. He had reloaded his gun and decided to kill the woman inside, he told police.

Austin wrenched open the driver’s side door. He ordered Ding out of the car. His plan, he confessed later to police, was to walk her into the foothills and shoot her there. He told her to turn off her phone. She threw the cell down, but when Austin bent to pick it up, she bolted into the darkness down the road.

Austin quickly squeezed off a round at the fleeing woman, police said. He missed. Austin wrapped both hands around the handgun, steadying his aim, but his second shot also skipped past Ding, he told police. By now, police had heard the gunfire in the canyon and were rushing to the scene. Austin ran back into the foothills.

The University of Utah campus was put on lockdown as hundreds of armed officers flooded into the area. Kathleen had actually gone to a campus building, where the staff called police. When they arrived, Austin’s wife told police her husband “had already killed someone, was in possession of two guns, had pistol-whipped her, and that he would kill someone for a vehicle,” police records say. The manhunt spread to the rest of Salt Lake City. Police later determined that Austin crawled from the scene through the underbrush on his belly, eventually coming in from the foothills north of the city, the AP reported.

The next afternoon, he was spotted roaming the halls of the Salt Lake City Public Library downtown, four miles from the canyon. A librarian noticed Austin, and security guards took him into custody in a third-floor bathroom, the Tribune reported. The same day, acting on a tip from Salt Lake police, law enforcement in Colorado discovered Ingle’s body in his trailer.

In interviews with police, both Boutains detailed Ingle’s slaying as well as the events leading up to Guo’s death.

On Thursday, Salt Lake County prosecutors charged Austin Boutain with 14 felonies, including aggravated murder, attempted murder, kidnapping and robbery. He faces the death penalty. Kathleen Boutain was charged with first-degree felony solicitation and second-degree theft. She could face life in prison if convicted.

Both remain in custody.

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