Marijuana legalization and workplace safety - Diamond and Diamond Lawyers

Marijuana legalization and workplace safety


The legalization of recreational use of marijuana in Canada has created safety concerns in many activities of everyday life, including driving and work. Use of marijuana when prescribed by a physician has been legal for two decades, but the increased number of people using marijuana following legalization of the drug for recreational use could put jeopardize worker safety with more drug-related accidents.

Studies of marijuana use and workplace safety

Legalization of recreational use of marijuana is too new to provide any clear data on its effects on Canadian workers. Studies of the subject in the U.S. where nine states and Washington, D.C., have legalized it for recreational use show a sharp rise in motor vehicle accidents linked to one or more of the drivers using marijuana.

At least one study revealed that workers who tested positive for marijuana had 55 percent more job-related accidents and 85 percent more injuries than workers with negative tests for marijuana. According to researchers, the effects of marijuana create different types and degrees of impairment depending upon the individual and whether it is inhaled, ingested or smoked. Some of the effects people might experience include the following:

  • Impaired depth perception
  • Slowed reaction time
  • Impaired motor skills and coordination
  • Distorted sensory perception, including colors appearing more vivid than normal and sounds appearing louder
  • Altered perception of time

The THC in marijuana is one of the chemicals responsible for the effects people experience from the drug. The levels of THC can be higher in some varieties of marijuana than in others, depending on the seeds and strains, and its effects could be affected by the frequency of a person’s use of the drug and how recently the drug was consumed.

Measuring marijuana impairment

If you drive a car in Ontario with a blood alcohol content of 0.08 percent or greater, you are in violation of the law for driving while intoxicated. The law is based upon scientific research supporting the establishment of a standard for intoxication from the consumption of alcohol. The scientific support for a similar standard to identify a person as being impaired by the use of marijuana is not as strong as it is for alcohol.

The impairment associated with cannabis use is generally related THC, which is one of the chemicals in marijuana. Creating a standard measure of impairment based upon THC levels has not met with a consensus of opinion among researchers because THC is detectable in a person long after using marijuana even though he or she is no longer impaired, so a positive work-related drug test indicting the presence of THC in an employee’s does not mean the person is unable to safely perform his or her work assignments.

Ontario sets rules for workplace use

Use of cannabis in a work setting is illegal in Ontario. The law recognizes that workers under the influence of marijuana pose a safety hazard to themselves and to others. Federal rules also prohibit the use of cannabis at work unless it is medically prescribed.

Canadian employers are required to have programs in place to ensure the safety of all workers against workplace hazards, including those related to workers showing signs of impairment from marijuana consumed outside of the workplace. An injury caused by the failure of an employer to enforce safety standards within the workplace could provide a right of compensation to someone suffering an injury in an accident.

Ontario personal injury lawyers

The personal injury lawyers at Diamond & Diamond have years of experience successfully handling claims for compensation by people injured in work-related accidents and incidents. If you suffer an injury caused by someone impaired by the use of marijuana, you should speak to one of our lawyers. Call the Diamond & Diamond 24/7 injury hotline at 1-800-567-HURT or visit our website to speak to someone now. We offer free consultations and case evaluations to injury victims throughout Ontario.

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