New documents have been filed in the case against a man formerly accused of killing three members of the Goggin family. Prosecutors will use the latest motion to revoke Kevin Harper's plea deal during a September hearing.

Harper was accused of murdering three members of the Goggin family in their West Valley home in 2011, but was offered a plea deal on lesser charges after prosecutors discovered they didn't have enough evidence against him. Now, that could all change. According to court documents, in November detectives got the statement they'd been waiting for from Crystal Gray West, the ex-wife of Harper.

West told detectives, "He goes I think I just killed three people."

When the detectives asked her if she knew how he did it, she responded "He said he remembers there was a big guy and he remembers swinging, that's all he remembers."

West also describes Harper coming home that night with a white SUV. She said he wanted her to follow him in a different car, but it wouldn't start. The ex-wife also remembers Harper having a scratch on one of his forearms and later noticed a car manual, a new pistol and some pieces of jewelry in their trailer.

West told detectives, "He just told me that he had gone to rob a house and that there was people there. And that the guy was big."

The motion also includes key statements from Randall Humphreys, an inmate housed in the same unit as Harper. Humphreys told detectives Harper admitted to the triple murder.

The inmate said, "He went in through the garage and went in through a sally port where he found himself a hammer."

The inmate also gave specific details about where Harper "framed" or beat several people inside the Goggin's family home.