Click or tap here to watch the entire press conference on the preliminary hearing presented by the district attorney 

CRIPPLE CREEK, Colo. - The Idaho nurse who claims she helped Patrick Frazee clean up the “horrific” crime scene after she said he murdered his fiancee Kelsey Berreth also intentionally left behind clues aimed at helping investigators crack the case. 

That’s according to testimony from Colorado Bureau of Investigation Agent Gregg Slater, who was the second and most explosive witness called during a preliminary hearing in Teller County court Tuesday morning. 

RELATED: Courtroom updates: Preliminary hearing for Patrick Frazee, who is accused of killing Kelsey Berreth

Frazee, who sat in the courtroom in a bulletproof vest and jail stripes, faces eight counts in the death of Berreth. The 29-year-old was last seen alive on Nov. 22 -- Thanksgiving Day.

A judge ruled Tuesday that there is enough evidence for Frazee to stand trial for the charges against him. He is slated to be arraigned on April 8 at 8:30 a.m.  

RELATED: Kelsey Berreth case: A timeline of events so far

Prosecutors announced new charges against Frazee during the hearing. In addition to first-degree murder and solicitation to commit first-degree murder, he now faces counts for tampering with a deceased human body and crime of violence, which is a sentence enhancer. 

Slater’s testimony detailed his lengthy conversations with Krystal Lee Kenney, the Idaho nurse who pleaded guilty to tampering with evidence earlier this month. As part of an agreement, she will testify against Frazee should the case come to trial. 

RELATED: 'I learned that Patrick Frazee had committed a homicide': Idaho nurse pleads guilty to moving Kelsey Berreth's cell phone

Kenney’s previous testimony revealed that she tampered with Berreth’s cellphone after her disappearance, but Slater discussed just how involved she claims she was during his multiple hours on the witness stand. 

Slater said investigators were able to corroborate many of the assertions made by Kenney, who told them Frazee had asked her to kill Berreth for months. She said she repeatedly backed out -- which prompted him to say that he would do it himself, Slater testified. 

On Thanksgiving, Slater said Kenney told him Frazee contacted her, and she knew that he had killed Berreth.

Kenney told Slater that Frazee said he beat his fiancee to death with a bat and then hid her body in a barn in a black tote box -- a piece of evidence that the prosecution called vital to the investigation. During the crime, Kenney told Slater the couple’s 1-year-old daughter was in a room nearby, according to his testimony. 

Frazee went to Thanksgiving dinner with his family that same night, according to Slater’s testimony. 

Kenney told Slater that once she learned what happened, she drove to Colorado with rubber gloves, a sanitary suit used for painting and bleach. 

According to Slater’s testimony, Kenney said she picked up the keys to Berreth’s home outside of Frazee’s house, and then drove to Woodland Park.

When she got inside Berreth’s home in the Colorado mountain town, she was confronted with an unthinkable scene. 

“Her words were when she opened the door, it was horrific,” Slater said. “She said she realized that ‘this had actually happened.’”  

Slater said Kenney told him there was blood everywhere. She was tasked with disposing of certain items -- including a bloody Bible and the sweater she claims Frazee used to cover Berreth’s eyes -- as well as wiping the blood off surfaces around the home.

But, Slater said Kenney also claimed she left some blood behind -- one of the multiple clues she hoped to leave investigators, even as she helped Frazee cover up his crime. 

According to Slater, when investigators returned to Berreth’s apartment with Kenney, she was able to point them to blood spatters they hadn’t seen before. 

She was also able to bring them to the barn where she said Frazee hid Berreth’s body, according to Slater. Inside that barn, Slater said a cadaver dog picked up a scent, and there was a discolored piece of hay where Kenney claimed the container with the victim’s body was stored. 

On Nov. 24, 2018 -- two days after Thanksgiving -- Kenney told Slater she and Frazee returned to the barn to collect Berreth’s body. She said they then returned to his property, where he put his fiancee in a trough and doused it with gasoline. According to Slater, Kenney said the ensuing fire grew so large at one point that Frazee’s mother went outside to check on what was happening. 

During Tuesday’s hearing, a judge ruled that Frazee’s mother does not have to testify at this point. 

Slater said when Kenney brought investigators back to Frazee’s property, they found evidence that a large burn had occurred there. Kenney told investigators that Frazee disposed of what was left of Berreth’s body in either a dumpster or a river, Slater said. 

Berreth’s body has not yet been found. 

Kenney told investigators that Frazee asked her to dispose of Berreth’s cellphone and gun, according to Slater. She said she drove back to Idaho on Nov. 24, but intentionally let both her and Berreth’s phone ping in Grand Junction, Salt Lake City and Gooding, Idaho, in hopes investigators could use the towers to track her town, Slater testified. 

Slater said Kenney claimed she burned Berreth’s phone in her front yard, but not before using it to text Berreth's mom to say she would “call her tomorrow.” She also sent a text to Berreth’s employer that said she wouldn’t be at work the following week, as she was visiting her grandmother in Washington. 

These were the last messages the phone ever sent, Slater said. 

In his testimony, Slater said Kenney did not initially cooperate with investigators, who tracked her down after seeing that she had called Frazee’s phone after Berreth went missing. 

But, after consulting with a lawyer, Kenney agreed to a long interview, where she admitted she began a romantic relationship with Frazee in March 2018, according to Slater. She said she didn’t know he had a child and a fiancee until that summer when she found out from a mutual friend of theirs. 

In the ensuing months, Slater said Kenney claimed Frazee told her he thought Berreth was a terrible mother who abused their child and abused alcohol. Slater also said police found no police or hospital records indicating the couple’s 1-year-old daughter was anything other than happy and healthy. 

At one point in September, Kenney said she and Frazee discussed poisoning a caramel macchiato and giving it to Berreth. In fact, according to Slater’s testimony, Kenney decided to do just that but opted not to, saying she didn’t want to hurt Berreth. 

Nevertheless, she gave her coffee and pretended to be a neighbor. They also exchanged numbers -- with hers belonging to a burner phone that was Frazee’s idea, Slater said Kenney told him. 

In the ensuing months, Kenney claimed Frazee asked her to beat Berreth to death with a bat, but she refused. 

Meanwhile, according to testimony from Woodland Park Police Department Officer Chris Adams, Berreth’s mom said she believed her daughter and Frazee were together, albeit with a non-traditional arrangement. 

Berreth worked as a flight instructor in Pueblo while Frazee worked on a ranch in Florissant.

During Adams’ testimony, the court heard a recorded interview with Frazee on Dec. 2 -- the day Berreth was reported missing. In the conversation, Frazee was heard saying that he and Berreth had broken up and exchanged their daughter at random locations depending on their work schedules. 

He said Berreth sought treatment for alcohol abuse, and that he last saw on her Thanksgiving when they exchanged custody of their daughter. 

Adams said Berreth’s mother claimed her daughter had been with Frazee the night before her disappearance. That evening, Berreth’s mother said her daughter called again to say Frazee had given her her gun back, and that she had gone target shooting. 

This was notable, according to Adams’ testimony, because Frazee first took away Berreth’s firearm in late 2017 after she made comments about taking her own life during a fight. 

But Slater said Kenney claimed Frazee tried to use the gun as a piece of evidence to make it appear that Berreth had taken her own life, rather than been the victim of foul play. 

Frazee was taken into custody on Dec. 21. In addition to the criminal case against him, he has also been involved in a custody dispute involving his and Berreth’s daughter, who remains in the custody of her parents and child protective services. 

RELATED: Daughter of Patrick Frazee, Kelsey Berreth to remain in custody of maternal grandparents

In a wrongful death lawsuit filed by Berreth’s parents, custody of the child is listed as what they believe motivated the crime. 

RELATED: Family: Custody of 1-year-old daughter was Patrick Frazee's motive in Kelsey Berreth murder

During Slater’s testimony, he alleged that investigators found custody documents inside of Frazee’s home dated in August 2018, but they had never been filed. 

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