A Vicious High: The Link Between Marijuana and Violence

Posted on August 8, 2022 View all news

The whole country, we’re seeing this increase in crime that goes hand in hand with a decrease in concern about things like substance abuse. The problem is, when you continue to desensitize the population against substance abuse, you start to desensitize them against a sense of right and wrong.”

~ Betsy Branter Smith, a retired Police Sergeant, and Spokeswoman for the National Police Association

One of the biggest arguments supporters of cannabis legalization like to use is the belief that marijuana makes people mellow, chills them out, and calms them down. They say that unlike, say, alcohol, it makes people less aggressive and violent. They even say that it makes crime rates go down.

But is that REALLY true?

There is a mountain of scientific evidence that suggests that marijuana triggers changes within the brain that make the user more prone to violence, and that mountain grows taller every day. 

Because recreational use has been legal in several states for a few years, researchers now have sufficient measurable data from which to draw, and the conclusions contradict the popular opinion that cannabis is harmless.

Here, we take a closer look at what we have learned about the link between marijuana and violence. 

What Evidence Exists That Marijuana Causes Violent Behavior?

“Marijuana use causes violent behavior through increased aggressiveness, paranoia, and personality changes (more suspicious, aggressive, and angry).”

~ The International Journal of Environmental Research and Public Health (IJERPA)

To understand marijuana’s potential to trigger violent behavior, you first have to understand what it does to the brain. Specifically, cannabis use triggers changes in the anterior cingulate cortex (ACC), the region of the brain responsible for emotional control and response to the behavior of others.

Of special relevance, when the ACC is affected, a user can have a shorter emotional fuse and be more prone to outbursts.

Both genetics and certain pre-existing conditions can increase the likelihood of aggression and violence in marijuana users. People with mood disorders or mutations to their cannabinoid receptors score higher on an anger scale after smoking pot.

All of these factors combine to explain why marijuana use is associated with a 7-fold increase in the odds of committing violent crimes, according to a 2016 study.

Even more recently, a 2020 meta-analysis involving 30 studies and nearly 300,000 participants concluded that “cannabis use appears to be a contributing factor in the perpetration of physical violence.”

Personal Assaults and Marijuana

High-potency marijuana is a predictable and preventable cause of tragic, violent consequences.”


A 2001 study revealed an at-the-time “unexpected association” – the more frequently an individual used marijuana, the more likely they were to commit a criminal offense involving a weapon.

Significantly, this association did not exist for any other illicit substance

As an example of what legalized marijuana brings, look at Colorado. Since 2012, the number and rate of aggravated assault and other violent crimes have increased significantly and are now higher than the US average.

This casts serious doubts on the claim that the legalization of marijuana has a positive impact on crime rates.

Marijuana and Self-Harm

One thing to consider is that people have this preconceived notion that smoking marijuana makes people mellow, but the products being sold now are not the same as the plant that people were smoking in the 70s. Potency has increased dramatically, and higher potency products may have different effects.”

~ University of California San Francisco (UCSF)

Violence – whether directed outward or inward – is always a concern. Researchers at UCSF’s Department of Epidemiology and Biostatistics have narrowed in on an underreported form of violence – self-harm.

According to the first-of-its-kind study, the legalization of recreational marijuana is associated with a corresponding 20% increase in self-harming injuries in men under the age of 40. Pointedly, that increase is greatest where marijuana is readily available at dispensaries.

This dovetails with earlier research that cannabis is linked with suicidal thoughts, planning, and attempts among young adults. The link was dose-specific – just 3% of people who do not use marijuana struggle with suicidal ideation, compared with 9% of daily users and 14% of people with Cannabis Use Disorder.

Domestic Violence and Marijuana

Consistent marijuana use was related to an increased risk of intimate partner violence perpetration.”

~ Journal of Interpersonal Violence

Contradicting the notion that marijuana has a calming effect, there is also an established correlation between marijuana use and domestic violence. This is not surprising, because if pot can affect the brain so profoundly as to make a person more violent, their target will be their partner more often than not.

How strong is the association?

According to a 2018 study, 60% of people in a Batterer’s Intervention Program admit to using marijuana during the previous year, and nearly 30% report smoking weed 4 or more times a week.

Significantly, the use of marijuana is positively and strongly associated with all forms of intimate partner violence – physical, sexual, and psychological. Moreover, it is a major factor even after controlling for other problems, such as alcohol abuse, relationship satisfaction, and symptoms of an antisocial personality disorder.  

Murder and Marijuana

The biggest way that marijuana fuels violent behavior is by causing the user to suffer from paranoia. The person feels like they are being persecuted or that someone is trying to harm them, so they lash out.

Users of highly potent edible products frequently report hallucinations, paranoia and actions based on such imaginary threats, according to the University of Colorado Hospital (UCHealth). They reported in 2018 that three deaths were linked to the consumption of marijuana edibles and hallucinations. A paper published in 2007 in the Medical Journal of Australia found that most murderers who killed someone during a psychotic episode reported feeling that they were in danger from their victim.  Two-thirds admitted to being regular marijuana users.

To put that in perspective, that was more than alcohol and amphetamines combined.

 An earlier study found that among people convicted of homicide, marijuana was the drug with the highest rate of lifetime use. One-third admitted to smoking pot within 24 hours before the murder was committed, and three-fourths of those were still feeling the effects at the time of the crime.

And as far as the oft-repeated claim by proponents of expanded legalization that marijuana would lower crime rates, look at the following real life examples:

  • Colorado (legalized in 2012) – Homicide rates have climbed steadily, and are at an all-time high.
  • Alaska (2014) – The number of homicides has gone up and in 2019, hit an almost 40-year high.
  • Washington (2014) – Murders are soaring in Washington State and hit a tragic new high in 2021. The number of state homicides in 2021 was 54%  higher than in 2014.
  • Washington, DC (2014) – Homicide is at its highest point in almost 20 years.
  • California (2016): Homicides in California haven’t been this high since 2007, with many cities seeing double-digit increases

If one of the hypothetical benefits of cannabis legalization is supposed to be a reduction in crime, why are so many states experiencing a record number of murders? 

Rape and Marijuana

The perpetrator knows marijuana or alcohol provides a kind of social cover, making it easier for him or her to assault a victim.”

~ Patricia Maarhuis, Coordinator of Alcohol and Drug Counseling, Assessment, and Prevention Services

Legally, cannabis is classified as a substance that can impair the user, which can negatively affect their ability to give consent. Because it lowers inhibitions and impairs judgment, it is labeled by the US Department of Health & Human Services as a date rape drug.

Marijuana is second only to alcohol as the substance most involved in sexual assaults where the victim is incapacitated.

It is a double-edged sword, because the victim can be too high to give consent or to judge safe situations, while the perpetrator is too impaired to read signals or judge consent.

But even when force is not used, having sex with someone who is too high to make responsible decisions is still rape. 

Mass Shootings and Marijuana: The Chilling Connection

“And, in all honesty, we cannot rule out a connection between increasing marijuana use, mental illness and the recent spate of mass shootings by disturbed young males.”

~ By Miranda Devine, New York Post journalist

Given what we know about marijuana’s ability to increase a user’s paranoia, hostility, and psychotic symptoms, it cannot logically be mere coincidence it is linked to so many mass shooters:

Given the multiple studies on marijuana and violence toward self and others, and the increasing evidence of these facts playing out in our society today, it is time that we admit that there is a problem and strive to address the issue before more people die unnecessarily. 

How YOU Can Help

In short, this Bill (CAOA) would be an enormous gift to cartels and gangs, and in the midst of a nationwide violent crime surge.”

~ US Senator Tom Cotton, speaking against Federal decriminalization on July 26, 2022

The science is clear – marijuana is not harmless, and increased legalization and easy availability creates a serious public health crisis. For every supposed benefit, there are numerous scientific studies that show the opposite.

YOU can help protect yourself, your family, and society by getting involved. Contact your local legislators, participate in public forums, and share accurate information that counters the stream of misinformation pushed by the pro-cannabis industry.

If you have not already, join the Every Brain Matters alliance, subscribe to our newsletter and podcast, and help spread the truth about the dangers of marijuana.



























Leave a Reply

Your email address will not be published. Required fields are marked *