DENVER (CBS4) – Another death in Colorado has been listed as having “marijuana intoxication” as a factor, according to a CBS4 investigation, and several other families are now saying they believed the deaths of their loved ones can be traced to recreational marijuana use.

Daniel Juarez, an 18-year-old from Brighton, died Sept. 26, 2012 after stabbing himself 20 times. In an autopsy report that had never been made public before, but was obtained by CBS4, his THC level — the active ingredient in marijuana — was measured at 38.2 nanograms. In Colorado, anything over 5 nanograms is considered impaired for driving.

Juarez was nearly eight times the legal limit.

“If he had not smoked marijuana that night he would still be here,” said his sister, Erika Juarez. “He was extremely high. There’s no other reason he would do it,” said his older sister.

According to police reports and interviews obtained by CBS4, Juarez and a friend were smoking marijuana that night when Juarez told his friend “he didn’t want anymore because he was too high.” Juarez, who was a standout soccer player for Brighton High School, then told his friend “I just had an epiphany.”

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Police and witnesses then say Juarez literally ran wild, stripping off most of his clothing and running into his nearby apartment. There, he got a knife and stabbed himself 20 times, one of the stab wounds piercing his heart. Juarez’s autopsy report lists his manner of death as suicide with “marijuana intoxication” as a “significant condition.”

A police report in the death notes that the THC in the teenager’s blood was “almost 11 times more than the average amount found in a male using marijuana.”

Police and medical personnel suspected the marijuana Juarez smoked might have been laced with methamphetamine or another substance that could have triggered the irrational behavior. The autopsy shows that tests were done for amphetamines, synthetic stimulants and synthetic cannabinoid drugs, but all those tests were negative.

“I lost my brother to it,” said Erika Juarez. “It’s not harmless, it can kill people and most people don’t see that.”

Up until now, just three other deaths in Colorado were seen as having links to marijuana. Levy Thamba Pongi, a 19-year-old college student jumped from a Denver balcony to his death in 2014 after eating marijuana edibles. Marijuana intoxication was listed as a factor in his death.

Richard Kirk of Denver is accused of killing his wife, Kristine. Before her death, she called police and said her husband seemed to be hallucinating after ingesting marijuana edibles and prescription medications.

And college student Luke Goodman killed himself in Keystone in March shortly after ingesting marijuana edibles. His mother told CBS4 she believes the marijuana caused her son to kill himself. An autopsy report showed Goodman’s THC level at 3.1 nanograms, below the impaired driving limit.

The Juarez case adds another to the list of death cases with links to marijuana.

CBS4 found another Colorado death with strong ties to recreational marijuana. On May 18, 2012, Tron Dohse was returning to his Thornton apartment after attending a Rockies game. When he arrived home he had apparently lost his keys so he attempted to climb the outside of the apartment building to get to his balcony and gain access to his apartment.

He fell to his death, which was ruled an accident.

According to his autopsy report obtained by CBS4, Dohse’s THC level was 27.3 nanograms, more than five times the Colorado limit for impaired driving.

An autopsy on the 26-year-old restaurant worker showed no other drugs or alcohol in his system. His older sister, Tori Castagna, told CBS4 she now believes marijuana impairment led her brother to make poor decisions the night of his death.

“I couldn’t believe how high the (THC) level was,” said Castagna. “I think it had a very strong impact on what he did that night. I think his judgment was completely skewed. I really believe that was the main contributor.”

According to a Thornton police report, the first officer to arrive wrote that he smelled “a strong odor of an unknown alcoholic beverage coming from his person/breath.” And a witness told police that prior to the late night fall, Dohse “was intoxicated.” But by the time Dohse’s blood was drawn, no alcohol was present, only an elevated level of THC.

“I do believe he was very impaired from that high level,” said Castagna. “We’re seeing more things like this that are showing how serious it can be.”

Dr. Chris Colwell, Chief of Emergency Medicine at Denver Health Medical Center, said since the legalization of recreational marijuana in Colorado, he has seen more and more cases like these of people who have ingested marijuana making poor decisions, decisions they would not otherwise make.

‘In some cases they will ingest marijuana and behave in a way we would describe as psychotic,” he said.

Colwell said several times each week people enter the Denver Health emergency department after ingesting marijuana and acting suicidal.

“We’ll see several of those every week … that we have to restrain to insure they aren’t a danger to themselves or other people,” Colwell said.

Colwell said after ingesting marijuana he has seen people jumping off balconies, driving at high speeds and driving erratically.

“They’re making decisions they would not have made when not under the influence of marijuana,” he said.

Colwell said recalled one particular case from last Halloween when a man ingested marijuana edibles, dressed up as Superman, and then jumped off a balcony, “Almost as if he could fly as the costume would imply.” Colwell said the man suffered seven fractures but survived.

“It was a very dangerous situation.”

He said later he didn’t know why he did what he did. Colwell said his ER is seeing more and more of the same issues from marijuana that it has historically seen from alcohol.

Marijuana activists call these kinds of stories scare tactics and say the problems associated with marijuana ingestion are infinitesimal when compared to alcohol and prescription drugs.

Mason Tvert, a pro-marijuana activist, said he wasn’t buying stories of suicides following pot ingestion.

“There is no evidence that using marijuana makes you want to kill yourself,” said Tvert. “There is no science, no research that says by using marijuana you are going to become suicidal. There is evidence that people who tend to be suicidal may be more likely to use marijuana.”

Tvert went on to say that the number of adverse incidents following the ingestion of marijuana are infinitesimal when compared to alcohol.

“The fact that we are talking about the handful of incidents over the past several years suggests that this is not an exceptionally large problem, but it is something that needs to be talked about,” he said.

Tvert said these deaths are “absolutely” being blown out of proportion by the media, especially when compared to deaths connected to alcohol.

In Boulder, eight years after her son’s death, Ann Clark believes her son’s own words show that marijuana led him to kill himself.

Her son Brant was a 17-year-old high school student who attended a party, and according to his mother, smoked a large amount of marijuana. She said that session caused a “major psychotic break. The changes in my son were so intense that in the next three days he required emergency care at two hospitals.”

Hospital documents examined by CBS4 from December 2007 say Brant told doctors, “Marijuana really messed me up.” Brant “reported feelings of paranoia after marijuana that he couldn’t shake.”

Three weeks later, Brant Clark took his own life leaving behind two notes, one for his mother and a second addressed to God.

“Sorry for what I have done I wasn’t thinking the night I smoked myself out’, the note said.

“I believe my son would be alive today if he had never used marijuana,” said Ann Clark.

In a 2014 article in the New England Journal of Medicine, doctors from the National Institutes of Health published an article entitled, “Adverse Health Effects of Marijuana Use” and wrote, “Both immediate exposure and long-term exposure to marijuana impair driving ability; marijuana is the illicit drug most frequently reported in connection with impaired driving and accidents, including fatal accidents. There is a relationship between the blood THC concentration and performance in controlled driving-simulation studies.”

The authors go on to write, “Recent marijuana smoking and blood THC levels of 2 to 5 ng per milliliter are associated with substantial driving impairment.”

The doctors who wrote the article concluded, “During intoxication, marijuana can interfere with cognitive function and motor function and these effects can have detrimental consequences.”

CBS4 Investigator Brian Maass has been with the station more than 30 years uncovering waste, fraud and corruption. Follow him on Twitter @Briancbs4.