STURGEON BAY, Wis. (AP) — A jury in Door County on Friday found an 86-year-old man guilty of killing his wife and disposing of her body more than four decades ago.

Jurors returned guilty verdicts on charges of first-degree murder and disinterment of the dead against Richard Pierce, who has maintained his innocence.

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Carol Jean Pierce has not been seen since Sept. 5, 1975 and her remains have never been found. Investigators say Richard Pierce moved to Cheboygan, Michigan shortly after his wife disappeared.

Investigators searched Pierce’s Michigan home in 2008. Prosecutors believe the Carol Jean Pierce’s body was hidden in the Michigan home for years until Richard Pierce removed it.

In September of 2018, the Wisconsin Cold Case Review Team looked at the case and concluded there was enough evidence to show Richard Pierce was set to gain from his wife’s disappearance, WBAY-TV reported.

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Investigators from Sturgeon Bay and Michigan then spent weeks searching Richard Pierce’s property in Michigan, looking for possible evidence related to the woman’s disappearance. Her remains were never located. However, a cadaver dog handler testified at trial that the dog had six hits for human remains in Pierce’s house.

The prosecution argued that Pierce would benefit from his wife’s death, getting her property, including a home and truck, and could move on with a new girlfriend.

Sentencing is scheduled Aug. 5.

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