DENVER (AP) – A Denver man accused of killing his wife after eating marijuana-infused candy he bought at a legal pot shop has pleaded not guilty to first-degree murder.

Richard Kirk, 48, entered his plea during a brief court appearance Friday as members of his family watched. He is charged with shooting Kristine Kirk, 44, last April while she was on a 911 call with police dispatchers.

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The shooting stoked concerns about the effects of the marijuana snacks, which have become popular since the state legalized recreational pot shops. Colorado lawmakers last year tightened regulations on edible marijuana, responding to the Kirk case and the death of a college student who jumped to his death after eating a potent marijuana cookie. Colorado now has stricter potency limits on edibles.

Defense attorneys have suggested that Kirk was so impaired by the “Karma Kandy Orange Ginger” that he may not have intended to kill his wife. She told dispatchers that he was acting more drunk than violent, crawling through a bedroom window and cutting his legs on broken glass.

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But prosecutors argue he had the wherewithal to remember the code to a locked gun safe and press the weapon to his wife’s head.

The couple had three young sons, who were home at the time of the killing.

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On the 911 call, Kristine Kirk said her husband was paranoid and hallucinating after eating pot candy he had purchased in one of Colorado’s recreational marijuana stores. Dispatchers heard the woman beg her husband not to retrieve a gun from a safe. Then they heard a gunshot and the line went quiet.

Denver police Detective Troy Bisgard testified during Kirk’s preliminary hearing last year that the only substance found in Kirk’s blood was THC, marijuana’s intoxicating chemical, but drew no conclusions about whether the drug influenced his erratic behavior. The detective said Kirk’s THC levels were relatively low, but defense attorney Shanelle Kindel argued the effects of marijuana can be felt in small amounts.

The couple’s marital and financial problems were escalating, and Kristine Kirk was covered by a $340,000 life insurance policy, Bisgard said. She had recently told friends she had grown afraid of her husband because they had been fighting so much.

Richard Kirk is scheduled to go on trial Oct. 26.

By SADIE GURMAN, Associated Press

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