Reality Check: Liberal candidate criticized for her views on marijuana, but are they true?

Marijuana is weighed at a medical marijuana dispensary, in Vancouver, Wednesday, Feb. 5, 2015.
Marijuana is weighed at a medical marijuana dispensary, in Vancouver, Wednesday, Feb. 5, 2015. THE CANADIAN PRESS/Jonathan Hayward

A Liberal candidate in British Columbia is reportedly standing by some controversial comments she made on Facebook about the safety and positive effects of marijuana use.

Joy Davies shared links on her public Facebook page in 2013 suggesting marijuana was linked to lower levels of domestic violence and has been used to cure some cancers.

But are either of those claims true?

Davies did not respond to requests for comment about this story.

In one post from 2014, she linked to a study and wrote “in a nutshell, more pot = less domestic violence in married couples.”

She linked to a 2014 study from University of Buffalo researchers that claimed increased use of marijuana during the first nine years of marriage resulted in lower rates of domestic violence.

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The study used data from 634 married couples over nine years starting in 1996, and controlled for things like demographic variables, behavioural problems, and alcohol use.

But, according to a report on the study in the Washington Post, the results are predictive and not necessarily causal – meaning the type of people who smoke are already less prone to committing domestic violence.

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The authors do make some connections though, including “marijuana may enhance positive affect which in turn could reduce the likelihood of conflict and aggression” as well as “decrease the likelihood of aggressive behaviour.”  That means, people who are high are less likely to get upset.

The authors also pointed out that increased marijuana use was associated with decreased violence in all but one category – married women who used marijuana and had been perpetrators of domestic violence. In that case, according to the study, frequent marijuana use was linked with higher rates of violence.

The study also pointed out that couples where both individuals used marijuana were the least likely to be violent. But, the authors admitted, that might be because they “share similar values.”

“It is possible that, similar to a drinking partnership, couples who use marijuana together may share similar values and social circles, and it is this similarity that is responsible for reducing the likelihood of conflict,” according to the study.

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The authors also limited the study to “newly married, heterosexual couples who were marrying for the first time.” It did not take into account same-sex couples, re-married couples, dating couples, or couples who had been married for a long period of time.

Marijuana legalization and regulation has been a plank in Justin Trudeau’s Liberal campaign and he stuck to that script Thursday when asked about Davies’ statements.  He added however that Davies’ views aren’t in line with the party.

“The views expressed by the individual in question, do not reflect the views of the Liberal party of Canada and certainly do not reflect my personal views,” he said during a press conference in British Columbia.

The second Facebook post, this one from September 2014, suggested cannabis hemp oil could be used to “fix” skin cancer. It’s a shared post from the creator of, a website which claims to offer alternatives to “western methods” of treating cancer – though the introductory blurb states “I am not a doctor, nor am I offering a cure to anyone.”

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She reportedly stood by the statement that “pot could cure brain tumours in children as well as melanoma” according to the Huffington Post.

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But does cannabis oil cure, or “fix” cancer? Simply put, there’s no proof.

“There is not enough evidence to show that cannabis extracts and synthetic cannabinoids can treat or cure cancer in humans. There are some studies that look at the effects of cannabinoids on cancer cells and in experimental animals. However, this research is still in the early stages and much more is needed before any conclusions can be made,” Robert Nuttall, the assistant director of Cancer Control Policy at the Canadian Cancer Society said in a statement.

There are some studies suggesting cannabis oil can trigger cell death, and stop cells from dividing.

But these studies were done in a lab and according to the United Kingdom’s Cancer Research organization, “petri dishes are not people.”

“Most chemicals that show promise in lab or animal experiments turn out not to work as well as hoped when tested in patients,” the organization said.

And what’s more, most of the lab experiments did not result in a “cured” cancer.

“For the experiments involving cells grown in the lab, a proportion of the cells are killed or stop growing, but some of them carry on. Similarly in animal experiments, there is no data that shows a 100 per cent success rate for cannabinoids. For example, most mice treated with cannabinoids will still have tumours, although the cancers may be growing more slowly and spread less in some of them,” according to the organization’s website.

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Clinical trials show a similarly dim picture of using cannabis to treat cancer.  There has been one clinical trial in which nine people with advanced brain cancer were given high doses of THC. They all died within a year but the cancers were advanced and there was no control group. Without that, it’s impossible to say, according to the UK cancer organization, whether the THC even extended their lives.

There is one case study of a 14-year-old girl at Sick Kids Hospital in Toronto who was treated with hemp oil and chemotherapy. She eventually died.

But while cannabis might not be useful in treating cancer, there has been significant study on how it can reduce pain and as a result, Canadians can be prescribed medical marijuana in various forms.