The fatal and tragic mass shooting at a Planned Parenthood in Colorado Springs last weekend, resulting in the death of three people and nine others being injured, has lead to a surge of anti-marijuana outcries from groups believing cannabis is associated with psychotic episodes.

The shooter Robert Dear was reported by the New York Times to be a cannabis user at one point in time and since then anti-cannabis advocates have jumped on the finding, linking it with other infamous perpetrators of horrific crimes who also used cannabis. “The latest mass shooter (Planned Parenthood clinic) appears to be a long-time marijuana user who, like (Paris attack suspect Salah) Abdeslam, was not especially religious according to ex-wife,” the interest group Parents Opposed to Pot posted on their Facebook page. “The link between Robert Dear, Dylann Roof, some Paris attackers, the Chattanooga shooter, Tim McVeigh — long persistent marijuana use and then finding an ideology to give them meaning.”

Stop Pot 2016, a similar group out of California, also chose to exploit the shooting’s headlines and exploit them for their group’s publicity.  “CO shooter was a POT smoking oddball! How can the FBI and ATF ignore another ‪#‎marijuana link to this deranged killer,” read a post on their Facebook page. This proclamation was made before it had been determined whether Dear recently or even habitually smoked pot (this still hasn’t been determined), much less whether that use might have had anything to do with his actions.

Activist Christine Tatum, the co-author of “Clearing the Haze: Helping Families Face Teen Addiction,” also took the opportunity to use the murder of three people as a megaphone for her beliefs and posted about it on social media. When contacted by The Cannabist to comment on her position, she pointed them to a recent article she had co-reported in the Colorado Springs Gazette. That article read:

“Adolescent exposure to marijuana doubles the risk of developing psychosis in adulthood — which includes seeing and hearing things that aren’t there and maintaining fixed, false beliefs not shared by the larger community, according to research published in Lancet in 2009. This finding first was reported in 1988 and has been replicated at least five times with studies controlling for dozens of possible, confounding variables — and all yielding similar results.”

Of course, “maintaining fixed, false beliefs not shared by the larger community,” could also include staunch and reductive conclusions concerning the link between marijuana and violent behavior. If one was to look at the ludicrously large number of mass shootings (350 so far in 2015, according to or the many, many terrorist attacks that occur throughout Europe and the Middle East on a regular basis, then you could find any correlation you want to. More than likely three or more of the hundreds of perpetrators of these crimes watched violent movies or drank alcohol to excess or ate too much junk food (all of which have at times been blamed for psychotic behavior). In fact, the fact these interest groups can only find three mass shooters who smoked weed argues against their case, as 49% of Americans have smoked pot, according to Pew Research.

The truth is that the link between using cannabis and mental illness can’t be completely ruled out. Smoking weed, especially during adolescence, has been found in some studies to significantly increase the risk of developing schizophrenia later in life. But the exploitative, generalizing, and unscientific claims made by parties such as Parents Opposed to Pot and Christine Tatum nullify those questions and turn the issue into a binary position on marijuana – it’s either good or bad. It can be either one, or a combination of the two, depending on the situation, just like nearly everything else in the world.