News of the plea deal for Jordan Graham, 22, came as a jury was set to hear closing arguments in her murder trial. A judge is still deciding whether to accept the agreement.
Under the plea deal, prosecutors would drop charges of first-degree murder and making false statements. Graham would face a maximum sentence of life in prison.
No sentencing date has been scheduled.
Prosecutors had alleged Graham was having second thoughts about her 8-day-old marriage to 25-year-old Cody Johnson when she lured him to a steep cliff in the park on July 7 and intentionally pushed him.
Defense attorneys wrapped up their case Thursday without the bride telling the jury in her own words what happened that summer night.
Graham did not take the witness stand to defend herself against charges of first-degree murder, second-degree murder and making false statements to authorities in the death of Cody Johnson.
Instead, Graham's attorneys showed the jurors pictures and videos of Graham smiling as she had her hair done and tried on her borrowed wedding dress, then videos of the June 29 wedding and the couple's first dance.
Those images attempted to chip away at the prosecution's image of Graham as a cold, dispassionate woman who didn't want to marry Johnson and then eight days later, led him to a dangerous precipice in the Montana park and deliberately pushed him to his death.
Elizabeth Shea, a musician whom Graham commissioned to write a song for their first dance, described Graham as very quiet and standoffish — until she was asked about her wedding.
"She would light up. She would smile," Shea testified.
Jurors also heard from Graham's longtime employer Sarah Bigelow. Graham was a nanny for Bigelow's two children for five years. Bigelow, who loaned Graham her wedding dress, said it was difficult for Graham to interact with people she didn't know, but that her two children loved Graham.
"She was always on time. She always took care of them very well. They love her," Bigelow said.
Both the prosecution and defense rested their cases Thursday after three and a-half days of testimony. Jurors were to hear closing arguments in the afternoon, and the panel is expected to begin deliberations today.
Johnson was reported missing on July 8. Graham initially said he left with friends the night before, but eventually told the FBI that Johnson died in a tragic accident during a heated argument.
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