A Utah man could spend the rest of his life behind bars for murdering a teenager who threatened to reveal that he had sexually abused her, the Salt Lake Tribune reports.

Shaun Patrick French, 26, pleaded guilty on Wednesday to first-degree aggravated murder in connection with the May 2018 death of 15-year-old Baleigh Bagshaw.

The charge carries a life prison sentence, but as part of the plea agreement, prosecutors said they would not seek the death penalty and also dismissed additional charges of sexual exploitation of a minor, aggravated burglary and witness tampering.

French had been living in Bagshaw’s home and had an illegal sexual relationship with the girl beginning when she was 14 and he was 23, according to the Deseret News.

The abuse lasted for more than a year until Bagshaw ended the abuse and her family subsequently kicked him out of their home.

However, French “refused to accept the breakup,” according to a statement of facts filed in court supporting the plea arrangement.

Bagshaw informed French that she was going to report him to authorities. On May 7, 2018, French called Bagshaw 13 times and also attempted to blackmail the girl’s mother using sexually explicit photographs he had of her daughter, according to KUTV.

Later that day, as Bagshaw called her mother after she arrived home from school—something she did everyday—French was waiting inside her home. He then attacked her by stabbing her and slashing her throat.

Bagshaw’s mother could hear the attack on the phone and called a neighbor, who dialed 911, according to police.

Police launched a manhunt for French, which lasted two days and ended with his capture in Colorado.

At Wednesday’s hearing, Bagshaw said he agreed to the guilty plea.

“Your honor, to be honest, it’s either this or the death penalty,” Bagshaw told the judge, according to the Deseret News, adding: “This is the only thing to do. Yeah. It’s either this or die.”

Sentencing is scheduled for August 25.

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