Rock Springs Man Charged With First-Degree Murder In Stabbing Of Girlfriend's Ex

The Sweetwater County Attorney’s Office on Tuesday announced a first-degree murder charge for a Rock Springs man who turned himself in after allegedly stabbing his girlfriend’s ex-boyfriend.

Clair McFarland

August 08, 20237 min read

William Thomas Brewer 8 8 24
(Cowboy State Daily Staff)

The Sweetwater County Attorney’s Office has charged a 32-year-old Rock Springs man with first-degree murder and concealing a dead body relating to a Teton County man’s death last month.  

Law enforcement agents already had a warrant for William Thomas Brewer’s arrest before passersby discovered the body of Colter Watsabaugh, 30, on a dirt side-road in Reliance on July 16, according to a Tuesday press release by the Sweetwater County Sheriff’s Office and Attorney’s Office.  

But Brewer turned himself in, according to his case affidavit.  

Watsabaugh’s death was a homicide, the statement says. 

Partially Buried 

Detective Matthew Wharton learned about a dead man near Tri-State Road in Reliance at about 2:15 p.m. on July 16, according to an evidentiary affidavit filed in the case.  

Wharton found Watsabaugh there, lying face down directly off the side of the dirt road. The body was partially buried with dirt, sticks and plant material, the affidavit says.  

Watsabaugh’s body also had several “significant edge weapon” slashes to both triceps regions and his head, the affidavit says, as well as blood on his face, arms, back, head and under his body.  

Blood flowed from where his head lay.  

By about 11:50 p.m., Travis Sanders, assistant Sweetwater County coroner, rotated the body and revealed a roughly 2-inch slash to his right cheek, from his right ear to the right side of his mouth. There also was a laceration to the right side of his chest, about 3 inches, the affidavit says, and another 3-inch slash on the right chest area. 

Whose Girlfriend? 

Wharton learned that Watsabaugh, Brewer and a woman were at another man’s house in Rock Springs before Watsabaugh’s death, the affidavit says. 

The document says Detective Sgt. Sheaman interviewed the woman, who said she and Brewer had been “hanging out for a month or so,” and she considered them to be dating.  

She was in a relationship with Watsabaugh previously, the affidavit says.  

Brewer reportedly knew about his girlfriend’s past relationship with Watsabaugh.  

On July 15 at about 10:15 p.m., the woman and Brewer left their friend’s house in her Honda to meet up with Watsabaugh at his motel room in Rock Springs, the affidavit says.  

Watsabaugh got into the backseat of her car, but after a couple of minutes he got out of the vehicle and left.  

The woman and Brewer went back to their friend’s house at about 11 p.m. The woman’s son asked about his Nintendo Switch, and she went outside to get it from her Honda, the affidavit says, but couldn’t find it.  

The affidavit says Brewer contacted Watsabaugh and asked if he’d seen the Nintendo Switch. Watsabaugh said he hadn’t.  

Brewer and the woman looked for the device, then went back to their friend’s house and hung out in the living room.  

Brewer told the woman he wanted to go to her home and change his shirt, and he left about 1:40 a.m. July 16, according to the affidavit. At about 2:01, Brewer and Watsabaugh came back to their friend’s house, where the woman was.  

Brewer said Watsabaugh wanted to tell her he didn’t steal the Nintendo Switch.  

The two men, their male host and the woman all went outside to smoke a cigarette, says the affidavit. Then the woman announced she needed to go to bed.  

Brewer volunteered to take Watsabaugh home in her Honda, the affidavit says.  

When the woman woke about 6 a.m., her Honda was gone, says the document. She tried to call Brewer but the number was not accepting calls.  

‘For Doing Something Bad’ 

Brewer arrived at the sheriff’s office lobby at 1:15 a.m. July 17.

“I want to turn myself in for doing something bad,” he allegedly said.  

Wharton arrived at the lobby and met with Brewer.

Brewer’s left pointer finger had a laceration about 1 inch long that appeared to be from an “edged weapon,” says the affidavit. Wharton spotted another cut to Brewer’s left wrist, also about an inch long.  

Wharton asked why Brewer was there.  

“To turn myself in, basically,” relates the affidavit. “I really don’t wanna say too much but I f***ed up and did something bad.” 

Wharton pressed for more information.  

“I can give you a  name, Colter,” said Brewer, allegedly. “You can put two and two together. It’s kinda f***ing me up a little bit. It’s gonna be for the rest of my life. … That’s why I’m here to try to make it right.” 

Brewer said he was  going to run because he was scared, “but it’s not worth it.”  

“I’m a f***ed up individual,” Brewer allegedly added. “I don’t know what happened, all I know is it was me.”  

Wharton asked Brewer how he go the cut on his hand.  

“I fell in the mountains,” Brewer responded, according to the affidavit. But he couldn’t recall where he was when he fell.  

Lung Wound 

A forensic pathologist on July 18 determined Watsabaugh died in a homicide due to a puncture wound to his right lung.  

Deputy Sheriff Jason Mower the next day found the woman’s Honda down a steep embankment off Sweetwater County Road No. 75.  

Wharton arrived and walked down to the Honda, which looked like it had been pushed off the roadway, according to the affidavit.  

There was blood on the front driver’s side window, windshield and front passenger-side floorboard. The directional blood spatter indicated two people were in the vehicle when the stabbing happened, and the doors were closed, the affidavit says.  

When county detectives and Wyoming Division of Criminal Investigation processed the vehicle for evidence, the document says they found Watsabaugh’s DC brand shoes, Columbia brand hat and keys on a lanyard.  

Don’t Sell Your Own Drugs 

Brewer had a prior bench warrant for his arrest after he reportedly shirked the terms of his three-year probation sentence from a 2021 felony burglary charge. An affidavit says he skipped out on his probation agent, left Rock Springs without permission, got drunk in Casper, sold his prescribed Suboxone to peers in his counseling program and left treatment early.  

Law enforcement agents arrested Brewer the day Brewer showed up in the sheriff’s office lobby on his outstanding warrant.  

Because of Brewer’s extensive criminal history, he also faces a habitual offender enhancement, the statement says. 

Habitual criminals face up to a life sentence in prison if they’ve been convicted of three felonies prior.  

The first-degree murder charge is punishable by life in prison without parole, or death.  

Hiding a dead body to cover a felony offense is punishable by up to 10 years in prison and $10,000 in fines.  

Clair McFarland can be reached at

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Clair McFarland

Crime and Courts Reporter