ADAMS COUNTY, Colo. (CBS4) – The man accused of killing a teenager from Broomfield pleaded guilty to second-degree murder in Natalie Bollinger’s death. Joseph Lopez made the plea in court on Monday morning.

Joseph Lopez (credit: Adams County)

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Bollinger disappeared on Dec. 28, 2017 and her body was found the following day on land belonging to McIntosh Dairy in Adams County. She was killed by a single gunshot wound to head, and it was also determined she had a lethal dose of heroin in her system.

Natalie Bollinger (credit: CBS4)

Bollinger’s father was able to speak in court at the sentencing hearing. He told the judge he did not agree with the plea deal offered to Lopez because he didn’t believe it was justice. Ted Bollinger also said that neither he nor his family were told about the plea agreement at the earliest date possible.

The judge denied his request to continue the hearing, saying that the prosecution had made several attempts to contact the Bollinger family.

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(credit: CBS4)

“What we took, we took because that was the most we could probably get without a jury agreeing 100 percent, because that’s what it would have taken for first-degree murder and life in prison,” said Natalie’s grandmother Denise Stuart.

Lopez, 23, told investigators that he met Bollinger through the classified advertisements website. He claims that she wanted to be shot and killed and that he tried to talk her out of it.

Joseph Lopez in court (credit: CBS)

Police arrested Lopez after investigators examined Bollinger’s social media accounts.

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Lopez told police that she shot herself but changed his story when he was told the coroner ruled her death a homicide. He faces nearly 50 years in prison.