MOUNT PLEASANT (WWJ/AP) – A mid-Michigan minister charged with killing his fiancée’s 24-year-old daughter in her mobile home as part of a sexual fantasy has pleaded guilty to second-degree murder in the case.

John D. White entered the plea Thursday in Isabella County Circuit Court in Mount Pleasant to second-degree murder and being a third-offense habitual offender. He’s expected to serve more than 45 years in prison under an agreement with prosecutors. Sentencing is scheduled for April 18.

Police say White, a 55-year-old ex-convict, confessed to killing Rebekah Gay as part of a sexual fantasy. According to an affidavit that was used in his arrest warrant, White admitted that for two weeks he thought about killing Gay and having sex with her dead body.

White, a self-proclaimed pastor who founded a church in rural western Isabella County, told investigators he went to Gay’s trailer about 2 a.m. on Oct. 31 after drinking about four or five beers, struck her head repeatedly with a mallet, then strangled her with a zip tie. He said he stripped her body but did not remember carrying out a sex act.

After using his pickup truck to move Gay’s body, the mallet and bloody towels, White returned to her trailer where he dressed Gay’s 3-year-old son in his Halloween costume and took him to an area Meijer store to be picked up by his father, a Midland resident, according to police.

Authorities say White led them to Gay’s body, which was found half a mile from her home in Isabella County’s Broomfield Township, after they told him her body was likely to deteriorate in the cold, wet weather.

Isabella County Sheriff Leo Mioduszewski said White had known Gay for some time and regularly watched her son while she worked, but was not a close friend. Mioduszewski said Gay’s son was home during the killing, but was unharmed.

“He kept saying he’s a bad person, he’s a pastor, he felt bad for the people in his church. … I don’t recall him being real remorseful at all with regard to the victim or anything else,” Mioduszewski said. “He just basically said he was attracted to her, thought she was a very cute girl. It’s a crazy, tragic situation.”

Donna Houghton, who had a role in hiring White at Christ Community Fellowship, said White had planned to marry Gay’s mother, who regularly attended his Sunday sermons. She also said she spoke to White before he was arrested, when he allegedly called her to ask that she contact other church members and start a prayer chain for Gay, who still was missing at the time.

White, who was originally charged with first-degree murder in Gay’s death, was released from prison in 2007 after serving nearly 12 years for manslaughter in the death of 26-year-old Vicky S. Wall in Kalamazoo County, according to the Michigan Department of Corrections. He also was sentenced to probation for choking and stabbing a 17-year-old Battle Creek girl in 1981.

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