Missouri Man Sentenced After Killing Grandfather He Claimed Was Poisoning Him: ‘He’ll Never Do It Again’

CENTERVIEW, MISSOURI — A Missouri man who shot and killed his grandfather after claiming the older man was “poisoning him” has been sentenced to 13 years in prison, according to court records.

Mastin Paul William Raines, now 23, pleaded guilty this week to voluntary manslaughter in the 2021 shooting death of 55-year-old William Mark Gustin at their home in Johnson County, roughly 55 miles southeast of Kansas City.

Grandson Admitted Shooting, Told Deputies ‘He’ll Never Do It Again’

According to an arrest affidavit obtained by the Warrensburg Star-Journal, Johnson County deputies responded on August 1, 2021, to reports of gunfire at a home in the 300 block of Southwest Highway 58.

When they arrived, Raines immediately approached deputies and said,

“He will never do it again.”

When asked who he was referring to, Raines replied,

“My grandfather. He’ll never do that again.”

Deputies entered the home and found Gustin dead on the living room floor, suffering from gunshot wounds to his stomach and neck. Investigators determined that Raines had fired at close range, with both bullets passing through the victim and into the floor.

Claimed Grandfather Was Poisoning Him

After being read his rights, Raines allegedly told detectives he believed his grandfather had been poisoning him for some time. He said he had decided that “today was the day” and loaded a rifle before drinking alcohol to build up the courage to carry out the shooting.

A witness inside the home told police they heard two gunshots and saw Raines holding the rifle. The witness hid in a bathroom until Raines calmed down and agreed to surrender the weapon.

Community Shock and Victim Remembered

According to his obituary, William Gustin owned a construction company and was known as an outdoorsman who enjoyed lake trips, motorcycling, and traveling to Branson with friends and family.

“He enjoyed spending time outdoors, trips to the lake and going to Branson; he especially enjoyed riding his motorcycle,” his obituary read.

Raines, who was 19 at the time of the shooting, will serve his 13-year prison sentence in the Missouri Department of Corrections.

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