The man accused of shooting and killing a 19-year-old Broomfield woman pleaded guilty to second-degree murder at a disposition hearing Monday morning.

Joseph Lopez, 23, told investigators that he shot Natalie Bollinger after responding to an ad she’d placed on Craigslist looking for someone to kill her, according to court documents previously obtained by 9Wants to Know.

Lopez has been sentenced to 48 years in prison plus five years probation as part of the plea deal.

Lopez had been scheduled to go to trial this week. However, according to Adams County court records, the trial had been vacated and a “disposition hearing” had been scheduled in its place at 9 a.m. Monday morning.

RELATED | Man charged with murder in Natalie Bollinger’s death

He faced a single count of first-degree murder after deliberation.

Bollinger was reported missing Dec. 28, 2017. The next day, her body was found along Riverdale Road in rural Adams County. She’d suffered a single gunshot wound to the head, although after an autopsy a toxicology test showed a “potentially lethal level of heroin” in her system.

According to court documents, Bollinger had a history of drug use and suicidal thoughts.

Natalie Bollinger
"Our family has been deeply devastated by this loss and cannot fully express how much we miss our beautiful Natalie. Our hearts are absolutely broken" wrote Ted Bollinger, Natalie's father.

Investigators’ biggest clue in the early days of the case was Bollinger’s cell phone, which showed more than 100 text messages between it and a phone number that eventually led detectives to Lopez, according to court records.

When Lopez was questioned, he told detectives he was looking at ads in the “women seeking men” section of Craigslist when he saw a post to the effect of “I want to put a hit on myself,” according to court documents. Lopez told detectives he eventually agreed to shoot her – apparently in exchange for being allowed to keep the 9mm handgun that belonged to her boyfriend as payment, according to the arrest affidavit.

BACKGROUND | Affidavit: Slain Broomfield woman put ad on Craigslist asking for someone to kill her

According to court records, Lopez told investigators he agreed to meet with Bollinger to kill or assist her in suicide. But said his goal was to convince the young woman not to go through with her plan, he told investigators, according to the affidavit.

Lopez’s arrest affidavit said he picked her up and that the two of them drove around, discussing how she “wanted to be shot and killed.”

Bollinger told Lopez she “wanted it to happen quickly” and that “she wanted to get on her knees and be executed from behind because she did not want to see the gun,” the affidavit said.

Lopez told investigators Bollinger provided the gun for him to use and told him she could keep it if he wanted to, according to court documents.

RELATED | 'I need to see justice served:' Mother of slain teen describes heartbreak

“Natalie Bollinger was a 19-year-old girl with her whole life ahead of her. The defendant was a

predator,” Chief Deputy District Attorney Ally Baber said at the sentencing hearing. “He didn’t respond as a human being. He responded as a predator.”

Contact 9NEWS reporter Kevin Vaughan with tips about this or any story: kevin.vaughan@9news.com or 303-871-1862.

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