LAKEWOOD, Colo. (CBS4)– The man accused of being behind the wheel when he caused a deadly crash that killed a mother and her young son had marijuana in his system.

Prosecutors in Jefferson County have charged Chris Cumsille with 10 counts including vehicular homicide in the deadly crash at Alameda Avenue and Oak Street in November 2017.

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An arrest affidavit says Cumsille told investigators he blacked out and doesn’t remember what happened.

(credit: CBS)

Information downloaded from his truck revealed he was traveling about 56 mph at the time of impact and never hit the brakes.

Anna Huffman, 43, of Lakewood was killed in the crash. Her 3-year-old son was seriously injured in the crash and rushed to Children’s Hospital where he later died.

(credit: CBS)

Detectives say Huffman and her young son were stopped at a red light inside their minivan when the driver of a truck, later identified as Cumsille, rear-ended them and caused a chain reaction with four other vehicles.

Chris Cumsille (credit: Jeffco DA)

Cumsille voluntarily submitted a blood test which revealed marijuana in his system.

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Prosecutors say he had 16 traffic violations.

The Colorado Department of Transportation says there is a growing concern and disturbing trend about the use of marijuana and driving.

Sam Cole (credit: CBS)

“Fatalities in Colorado that involve marijuana are increasing. They’re increasing probably about 20 percent every year,” said CDOT spokesman, Sam Cole. “We’re only four years into the legalization of marijuana in Colorado, so a lot of marijuana users don’t understand the dangers that they’re putting themselves and as well as the public when it comes to driving impaired.”

CDOT is hoping to find a solution to the driving high issue by having a conversation with marijuana users around the state.

In the coming weeks, CDOT will officially launch The Cannabis Conversation initiative. It will include online surveys and community meetings to learn why many pot users choose to get high and drive, what it would take to convince them not to and what the public perceives as the dangers of driving while impaired by marijuana.

LINK: The Cannabis Conversation Initiative 

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