AKRON -- An Ohio man says he decided to shoot his wife of 45 years in her hospital bed after she appeared to be in pain during a visit and he saw a tear run down her cheek.

John Wise testified Thursday at his Akron murder trial. He told jurors how he returned to the hospital hours after that unsettling visit, kissed his wife on the cheek and then shot her.

The 68-year-old Massillon man is pursuing an insanity defense in the August 2012 slaying. Friends of the couple have called it a mercy killing.

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A psychologist has testified that Wise showed signs of depression and other problems and wasn't fully aware of the unlawfulness of his actions.

Prosecutors contend Wise acted intentionally and should be held responsible.