Kenneth Pautler (Jefferson County Jail).

A 73-year-old Missouri man is behind bars after he allegedly shot his wife to death because he was “exhausted” of caring for her and did not want her to die in a nursing home.

Kenneth Pautler stands accused of first-degree murder and armed criminal action in the death of his 75-year-old wife Karen Pautler. The Jefferson County Sheriff’s Office said in a press release its deputies responded around 2:15 p.m. Friday to a home on Frontier Lane in Fenton, a suburb of St. Louis.

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When they arrived, Kenneth Pautler met them at the door and let them inside. They found Karen Pautler dead in a bedroom with a gunshot wound. According to a probable cause arrest affidavit obtained by local CBS affiliate KMOV and the St. Louis Post-Dispatch, the suspect gave cops the gun he used and admitted to shooting her. He allegedly said over the last few days he became “exhausted” of caring for his wife who had mental heath issues and he did not want her to die in a nursing home.

Police say on Friday morning, he decided to kill her.

“Kenneth advised he wanted the victim’s death to be humane, so he chose a specific cartridge for the firearm,” detectives reportedly wrote in the affidavit. “Kenneth also stated he chose his shot placement to kill the victim as quick as possible.”