Richard Kirk

Richard Kirk, 47, is suspected of shooting and killing his wife Monday night. (Denver Police Department / April 15, 2014)

Denver police are investigating whether a man suspected of fatally shooting his wife Monday night had been acting strangely because he may have consumed edible marijuana, a law enforcement official said Tuesday.

Richard Kirk’s wife called 911 to report that her husband was "talking about the end of the world" and hallucinating, behavior that was scaring their three children, according to a Denver Police Department arrest warrant.

The woman, whose name was redacted from the warrant, told the dispatcher that Kirk wanted her to shoot him. Eventually, he retrieved a gun from a safe, screamed and then a gunshot is heard on the 911 tape, according to the court document. Officers found the woman lying on the floor of the couple’s home, dead from an apparent gunshot to the head.

Although not mentioned in the arrest warrant, police said Tuesday that the woman also told the dispatcher that Kirk, 47, may have consumed edible marijuana. Denver police spokesman Sonny Jackson told the Los Angeles Times that the suspect's possible pot use was part of the homicide investigation.

Jackson told The Times that the 911 call would not be released during the investigation.

[Updated, 6:30 p.m. April 15: The 911 call lasted 12 to 13 minutes, police spokeswoman Raquel Lopez told The Times. She wasn’t sure whether the call ended when the wife stopped responding or when the officers arrived.

As Kirk sat in the back seat of a patrol car Monday night, he admitted to killing his wife without questioning from the arresting officer, the court document said.

The homicide was the first in several years in the upscale Observatory Park neighborhood east of the University of Denver, police said.

Kirk, who is being held in jail in lieu of bond, is scheduled to appear in court Wednesday morning, according to jail records. He was arrested on suspicion of first-degree murder, but has not been formally charged.

Crimes potentially involving marijuana are being closely watched in Colorado, which legalized recreational use of the drug this year. Last month, the Denver coroner’s office linked the suicide of a 19-year-old college student to marijuana intoxication. He had eaten a marijuana-laced cookie before jumping off a balcony.

Colorado lawmakers are considering measures to restrict the sale of edibles, including limiting the amount of marijuana baked into them and requiring labeling to keep edibles out of the mouths of children.

The limits measure, which on Tuesday passed through its first committee hearing, would ban marijuana customers from buying more than an ounce, whether through the typical bud or through edibles. Current law limits the potency per serving in edibles, but doesn't limit the purchasable weight.

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