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Toward the legalization, regulation and restriction of access to marijuana: Discussion paper – 2. Background

2. Background

A brief overview of marijuana

The cannabis plant is found throughout the world, but has its origins in Asia. It has been used for millennia for its psychoactive effects-euphoria ("the high"), relaxation, a sense of well-being, and intensification of ordinary sensory experiences (i.e., sight, sound, taste, smell). However, it has also historically been used for medical and social purposes.

A variety of products can be produced or derived from the flower of the cannabis plant including:

  • dried herbal material (i.e., "marijuana");
  • oil (e.g., "hash oil");
  • hash (i.e., compressed resin);
  • concentrates (e.g., "shatter"); or,
  • foods and beverages containing extracts of cannabis.

Cannabis is most often smoked (as a dried herbal product, either alone or as a concentrate mixed with tobacco), but it can also be vaporized, or eaten.

Cannabis contains hundreds of chemical substances, among which are over 100 known as "cannabinoids." Cannabinoids are a class of chemical compounds that act on receptors in cells in the brain and body. The most well-studied cannabinoid is THC (tetrahydrocannabinol), the primary psychoactive compound of cannabis (i.e., the chemical responsible for the "high"). Increasing attention is also being paid to another key cannabinoid-CBD (cannabidiol). Unlike THC, CBD is not psychoactive and may in fact counteract some of the psychoactive effects of THC. There is increasing scientific study into the potential therapeutic uses of CBD.

For the purposes of this discussion paper, the popular term "marijuana" is used throughout, unless a specific reference to a marijuana derivative product is being made.

Prevalence of use

Marijuana is the world's most used illicit psychoactive substance. Estimates from the United Nations Office on Drugs and Crime (UNODC) suggest that around 200 million people globally reported using marijuana at least once in 2012. A UNICEF report published in 2013 ranked Canada highest amongst all nations in terms of rates of marijuana use among youth.

Marijuana has been prohibited in Canada since the 1920s and is listed as a controlled substance in Schedule II of the Controlled Drugs and Substances Act (CDSA). As a result, possession, production and trafficking of marijuana are illegal. The Marihuana for Medical Purposes Regulations (MMPR) provide a regime allowing for legal access to marijuana for medical purposes.

Despite these prohibitions, marijuana remains the most commonly used illicit substance in Canada. It is the second most used recreational drug in Canada after alcohol, especially among youth. An estimated 22 million Canadians 15 years of age and older, approximately 75% of the population, drank alcohol in 2013. In contrast, eleven per cent of Canadians aged 15 or older reported having used marijuana at least once in 2013. When examined more closely, the data reveals that 8% of adults over the age of 25 reported past-year use of marijuana in 2013, whereas 25% of youth aged 15-24 reported past-year use.

The criminal justice system

Marijuana is the most trafficked drug in the world. In Canada alone the illegal trade of marijuana reaps an estimated $7 billion in income annually for organized crime. In addition, the administrative burden and social harms associated with the enforcement of marijuana laws, particularly for simple possession, are onerous, and need to be balanced with other safety priorities. Some Canadians argue that these laws are disproportionate to the seriousness of marijuana use as a criminal offence.

The current approach also creates challenges for the criminal justice system and for Canadians. Significant resources are required to prosecute simple possession offences. In 2014, marijuana possession offences accounted for 57,314 police-reported drug offences under the CDSA; this is more than half of police-reported drug offences. Of these, 22,223 resulted in a charge for possession that year.

The criminal records that result from these charges have serious implications for the individuals involved. People with criminal records may have difficulty finding employment and housing, and may be prevented from travelling outside of Canada. On a larger scale, criminal justice system resources are required to address the involvement of organized crime in the illicit marijuana market. In 2015, the Criminal Intelligence Service Canada reported 657 organized crime groups operating in Canada, of which over half are known or suspected to be involved in the illicit marijuana market.

The link between organized crime and the illicit marijuana market is well established. Due to the popularity of the drug among the general public, profitability, and the relative ease of production and cultivation, several significant Canadian-based organized crime groups and networks are involved in the production and distribution of marijuana. The majority of marijuana in the Canadian illicit market is believed to be produced domestically. In 2013, Health Canada reported that Canadian law enforcement sought destruction for over 39 metric tonnes of dried marijuana and more than 800,000 marijuana plants. As well, illicit marijuana grow operations exist in all parts of Canada and in all types of communities. Marijuana also moves across our borders, and according to the Canada Border Services Agency, between 2007 and 2012 marijuana was one of the top three types of drugs involved in drug seizure operations.

Police and the court system must also deal with individuals who drive while impaired by marijuana. In 2013, 97% of police-reported impaired driving incidents involved alcohol and 3% involved drugs (including marijuana), an increase from the reported 2% in 2011.

The Canadian Centre on Substance Abuse estimated that, based on 2002 data, public costs associated with the administration of justice for illicit drug use (including police, prosecutors, courts, correctional services) amounted to approximately $2.3 billion annually.

Health effects

There are both health risks and potential therapeutic benefits from marijuana. Most of the research on marijuana over the past five decades has focused on harms, with much less attention placed on potential therapeutic benefits. The illegal status of marijuana has made it difficult to draw a complete picture of the harms of its use compared to those associated with alcohol or tobacco use, or other psychoactive substances. The following summary is based on the current available evidence.

Health risks

In general, health risks associated with marijuana use can be acute (i.e., immediate and short-lived) or chronic (i.e., delayed and longer-lasting). However, the risks may increase significantly depending on a number of factors, including:

  • age at which use begins;
  • frequency of use;
  • duration of use;
  • amount used and potency of the product;
  • a user's actions while intoxicated, such as driving or consuming other substances or medications; and,
  • a user's health status and medical, personal, and family health history.

More specifically:

  • Frequency of use: Daily or near-daily use of marijuana can have serious long-term effects on a user's health, including risk of addiction, earlier onset or worsening of some mental illnesses in vulnerable individuals, and difficulty thinking, learning, remembering, and making decisions. Such effects may take days, weeks, months or years to resolve after use is stopped, depending on how long one has been using and when use began. Regular smoking can also harm the lungs.
  • Age at which use begins: Health risks associated with marijuana use during adolescence and young adulthood, when brains are still developing, can have greater long-term harm than use during adulthood. This can include the potential for addiction, long-lasting negative effects on proper cognitive and intellectual development, harms to mental health, poor educational outcomes, and reduced life satisfaction and achievement. There is good evidence that regular marijuana use that begins in early adolescence can harm scholastic achievement, and increase the risk of dropping out of school.
  • Individual health status: Besides youth, other people who are more vulnerable to the risks and harms of marijuana include those with a history of drug abuse/addiction, childhood abuse, trauma or neglect, people with certain mental illnesses and mood disorders, and children whose mothers used marijuana during pregnancy. Early and regular marijuana use has been associated with an increased risk of psychosis and schizophrenia, especially in those who have a personal or family history of such mental illnesses. In individuals with a history of psychiatric illness, use of marijuana can worsen the illness and complicate treatment.

Perception of risk

Despite increased risks for adolescents who use marijuana, the 2015 Ontario Student Drug Use and Health Survey reported that, among adolescents, the perceived risk of harm associated with marijuana use is actually decreasing. Others have observed that there is an inverse relationship between perception of risk and actual use (i.e., use of marijuana would go up as more people perceive it to be low risk).

Comparison with other psychoactive substances

The illegal status of marijuana makes it difficult to draw a complete picture of the harms of marijuana use compared to those associated with alcohol, tobacco or other psychoactive substances. The most well-established long term harm of regular marijuana use is addiction. Nevertheless, based on what is currently known, the risk of marijuana addiction is lower than the risk of addiction to alcohol, tobacco or opioids. And, unlike substances such as alcohol or opioids where overdoses may be fatal, a marijuana overdose is not fatal.

The "gateway" theory

Marijuana has often been dubbed the "gateway drug" — a stop on the way to the use of more harmful drugs and more serious drug addiction.

The so-called "gateway hypothesis" was popular in the 1970s/80s and neatly described a specific, progressive and hierarchical sequence of stages of drug use that begins with the use of a "softer drug" (e.g., marijuana) and escalates to use of "harder drugs" (e.g., cocaine).

However, over the years, many exceptions to and problems with the "gateway hypothesis" have surfaced. Because of this, the validity and relevance of this hypothesis have been challenged. There is now evidence that suggests that complex interactions among various individual/ predisposing factors and environmental factors (e.g., peer-pressure, family influence, drug availability, opportunities for drug use) drive drug seeking, drug use/abuse, and drug addiction, and these interactions are not necessarily tied to marijuana use alone.

Therapeutic benefits

With respect to claims of marijuana's therapeutic benefits, aside from clinical studies with marijuana-derived products that have received market authorization in Canada (i.e., Marinol®, Cesamet®, Sativex®), only a limited amount of credible clinical evidence exists.

Some clinical studies suggest that strains containing mainly THC have potential therapeutic benefits for some medical conditions, including:

  • severe nausea and vomiting associated with chemotherapy;
  • poor appetite and significant weight loss as a result of serious long-term or terminal disease (e.g., cancer, HIV/AIDS);
  • certain types of severe chronic pain (e.g., neuropathic);
  • symptoms associated with inflammatory bowel disease;
  • insomnia and anxiety/depression associated with serious long-term disease;
  • muscle spasms associated with multiple sclerosis; and,
  • symptoms encountered in palliative care settings.

Emerging evidence also suggests that marijuana strains containing mainly CBD may be useful in treating treatment-resistant epilepsy in children and adults.

Global context and International Obligations

Canada is a Party to three United Nations (UN) Conventions on narcotic drugsFootnote 1. In the context of the Convention, Canada is obliged to criminalize the production, sale and possession of cannabis for non-medical and non-scientific purposes.  Legalization of marijuana is not in keeping with the expressed purposes of the drug conventions.

While illegal in most countries, the approach to marijuana is shifting in some jurisdictions. Twenty-two countries have adopted some form of decriminalization (Decriminalizing marijuana means that it is still illegal but criminal sanctions have been replaced by fines or other types of penalties. This is a separate concept from legalization.) This decriminalization has taken effect either in law or through policies, guidelines and/or enforcement discretion. Decriminalization is viewed, by most observers, as consistent with the drug conventions, particularly where it involves personal consumption of small amounts of "soft drugs".

Despite this emerging shift globally in approaches to controlling and minimizing harms associated with marijuana use, Uruguay remains the only country that has fully legalized marijuana to date.

At a federal level, the United States' government continues to express opposition to the legalization of marijuana and it remains illegal in federal law.  However, the question of legalizing marijuana use is increasingly being posed by State legislators, despite the fact that it remains illegal under federal law. Currently, four States as well as the District of Columbia have legalized access to marijuana, and several more States will vote on similar propositions in 2016 and 2017. Lessons learned from the recent experiences of the states of Colorado and Washington, and from Uruguay, can be useful when considering the new system for Canada.

Some of the key lessons learned that have been reported from the Colorado and Washington State experiences include:

  • Identify clear and measurable objectives;
  • Develop a comprehensive regulatory system that controls product formats; that prevents commercialization through advertising controls; that prevents use by youth;
  • Allow for effective implementation by:
    • Take time needed for an effective launch;
    • Develop clear and comprehensive public communications;
    • Establish a strong evidence base and data collection strategy to enable long-term monitoring and adjustments to meet policy objectives; and,
    • Undertake public health education before legalization begins.

When contemplating changes to the illegal status of marijuana, countries must also give due consideration to the rule of law and to their obligations under the UN conventions. This dynamic international environment requires that consultations occur with the global community as Canada moves toward the legalization of marijuana, including with the International Narcotics Control Board (INCB) and the United States. While Canada's proposal to legalize marijuana may differ from drug control policy in other countries, it shares the objectives of protecting citizens, particularly youth; implementing evidence-based policy; and putting health and welfare at the centre of a balanced approach to treaty implementation. Canada is committed to respecting international partners and to seeking common ground in pursuit of these objectives.

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