In a Denver courtroom on March 13, a man named Richard Kirk pleaded not guilty to the first-degree murder of his wife, Kristine. He doesn't dispute that he killed her—according to the statement of probable cause, Kirk, without being questioned, told the officer arresting him that he had killed his wife. But Kirk's attorneys argue that the legally purchased marijuana edible he had consumed before the incident had so clouded his mind that he couldn't be held culpable for his actions.
Even in a state still grappling with how to handle legalized marijuana, it seems like an awful lot of responsibility to heap on a product called Karma Kandy Orange Ginger—the candy that, according to the search warrant affidavit obtained by VICE, was listed on a receipt found in the Kirks' basement on the night of the murder.
Troy Bisgard, the Denver Homicide Unit detective who responded to the scene last April, testified last year that there was a small amount—the exactly level was unspecified—of THC (and no other controlled substance) found in Kirk's blood; he did not speculate as to whether this played a role in the murder.
According to the affidavit, Denver police officers were dispatched to the Kirk residence around 9:30 PM on April 14, 2014. Officially, it was a domestic disturbance call—Kristine had told the 9-1-1 dispatcher that her husband was talking about the end of the world and was begging her to shoot him; he was holding a gun they normally kept in a locked safe. Kristine went on to say that her husband had eaten marijuana edibles, she believed he was hallucinating, and that he was terrifying the couple's three young children. At the end of the 9-1-1 call, Kristine screamed and then, after an apparent gunshot, the line went silent. She was pronounced dead on the scene at 9:58 PM.
According to local news reports from last fall, friends of the couple say Richard began being verbally abusive to Kristine at least six weeks before the shooting. This was around the time he started putting his paychecks in a private account rather than the couple's joint account. In addition to what friends reported to be a massive amount of credit card debt, a public records search conducted by VICE indicated that Richard had been on the receiving end of three tax liens from the IRS, the last two being issued in 2010. According to a report from CBS last year, a detective testified that Kristine was covered by a $340,000 life insurance policy.
In short, there seems to have been more than enough discord in the Kirk household to point to a possible motive—which might well discredit the "pot made me do it" argument. But there are those who believe there could be some merit in Kirk's likely marijuana defense. Karen Steinhauser, a Colorado legal analyst, told Denver's CBS affiliate over the weekend that there is precedent for a certain kind of intoxication as "a complete defense to a charge."
"[When] the substances produce an effect that was not anticipated," Steinhauser said, "then you have an involuntary intoxication." Such a scenario might mean Kirk would not be held legally responsible for his wife's murder.
So just how likely is it that THC affected Kirk so aggressively and adversely? In 2014, the year recreational marijuana became legal to sell, purchase, and possess in Colorado, there were at least 56 calls to the Rocky Mountain Poison and Drug Center from adults 19 and older that were believed to be related to marijuana. There have also been some high-profile cases of edibles in particular causing distress. Most famously, Levy Pongi, a 19-year-old exchange student from the Democratic Republic of the Congo, ate a single cookie that contained what is believed to be more than six standard dosages of THC, then leapt to his death out of a fourth-story window.
In the wake of Pongi's death and the Kirk killing, Barbara Brohl, the executive director of the Colorado Department of Revenue State Licensing Authority, signed a set of emergency rules governing the labeling and sale of edibles last July. The rules stipulate that one "serving" of THC be limited to ten milligrams, and that products that contain multiple servings be clearly indicated. Richard Kirk's public defender claims that, prior to the his wife's death, Kirk consumed 100 milligrams of THC—in other words, enough to send any ordinary pot user completely round the bend. (It is unknown how much experience he had with marijuana and edibles.)
But would that be enough to make Kirk hallucinate, as his wife said he did moments before he killed her? Dr. Cheryl Corcoran, who studies biological markers of risk and illness progression in schizophrenia at Columbia, has written that that marijuana can cause hallucinations in approximately one in every seven people. The National Institute of Health says that too much weed can indeed cause "auditory hallucinations, paranoid feelings of being persecuted, depersonalization, derealization, anxiety, grandiosity, irritability."
Richard Kirk's trial begins October 26. No matter the outcome, it's unlikely to change the legal status of legal marijuana in Colorado—not with the tax revenue from pot sales being used to fund substance abuse programs in schools. But it could well serve as a point of contention in states where battles over legalization rage on.
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