DENVER – The Denver man who pleaded guilty to killing his wife while investigators say he was high on marijuana edibles was sentenced Friday afternoon – nearly three years after the deadly attack.

Richard Kirk, 50, was sentenced to 30 years in prison and five years of parole for shooting and killing his wife Kris in April 2014 inside their DU-area home. He will get credit for time served. 

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Richard Kirk addressed the court during the sentencing hearing. Kris’ family left the courtroom to avoid listening to him.

Kirk blamed his actions the night of April 14, 2014 on marijuana. He said he shot his wife in the head “unknowingly.”

Kirk said he didn’t know how the edible would affect him when he purchased it.

His defense attorney said Kirk struggled with Opioid addiction that started with his back ache. The attorney said Kirk tried the marijuana candy to ease his back pain and try to get off the pills.

“If I had not ingested that marijuana edible, I would not have made the decision I made that night,” Kirk told the judge Friday.

Kirk said he loved his family and his sons and “that will never change.”

“I am sorry for becoming the monster I was supposed to protect them (his sons) from,” Kirk said. “Kris was the love of my life and my best friend. I will always love her.”

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Kirk was set to go to trial on first-degree murder charges, but took a plea deal for second-degree murder instead. If he was convicted on the first charge, he would have faced life in prison.

Kris Kirk was on the phone with a 911 operator when her husband shot her in the head. Their three young children were home at the time.

As part of the plea agreement, Richard Kirk agreed to relinquish parental rights to his children, who will be adopted by Kris Kirk’s parents.

Police and court documents say Kirk ate a pot edible before the shooting. Before she died, Kris told 911 she hadn’t seen him behave like he did that night in their 15 years of marriage.

Richard Kirk’s plea has changed multiple times. He originally pleaded not guilty, and then he changed his plea to not guilty by reason of insanity.

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According to court documents obtained by 9Wants to Know, Kirk’s defense was going to claim the marijuana caused his “delirium and psychotic-like symptoms”.

During the sentencing hearing Kris' family read the below impact statement and poems written by two of the Kirk sons.

Impact statement by Kris Kirk family by 9news on Scribd