Charging documents suggest Jordan Linn Graham, 22, was having second thoughts about getting married around the time the body of her husband, Cody Lee Johnson, 25, of Kalispell, was discovered.
Graham told an FBI agent that she and her husband had been arguing July 7 as they walked in the Loop Trail area of the park.
At one point, she turned to walk away, but Johnson grabbed her arm, she said. She turned around, removed his hand from her arm and "due to her anger, she pushed Johnson with both hands in the back, and as a result, he fell face first off the cliff," an affidavit states.
Johnson was reported missing July 8 when he failed to show up for work. Graham later reported that she had spotted his body.
Graham made an initial court appearance Monday before U.S. Magistrate Judge Jeremiah C. Lynch on a charge of second-degree murder. She is currently in custody.
Her attorney, public defender Andrew Nelson, declined to comment.
Johnson's family and friends were relieved after calling for an investigation since his body was recovered July 12.
"Two months probably isn't very long for an FBI investigation, but when you're waiting for answers, that's a lifetime," family friend Tracey Maness said.
Maness said Johnson was excited about his wedding and in love with Graham.
Graham initially told investigators that Johnson left their house late July 7 with unidentified friends in a dark-colored car with Washington state license plates.
That night, she texted a friend and said she was about to talk to Johnson about her reservations about having gotten married the previous weekend.
The friend, identified only by initials, told the FBI about receiving the text from Graham just before 9 p.m. in which Graham said, "Oh well, I'm going to talk to him."
The friend responded, "I'll pray for you guys."
Graham replied, "But dead serious if u don't hear from me at all again tonight, something happened."
Another friend said Graham reported receiving an email July 10 saying Johnson had left with three friends, went hiking, had fallen and was dead.
The next day, Graham reported to park officials that she had spotted Johnson's body. A ranger thought that was unusual, but Graham explained, "It was a place he wanted to see before he died," authorities said.
Graham was interviewed July 16 and acknowledged lying about her husband's death, authorities said.
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