Drug & Alcohol Testing, Part 1: What Are the Legal Limits on Testing Policies?


Workers who do their jobs while under the influence of drugs and alcohol pose a safety risk to themselves and their co-workers. To address this risk, many employers rely on drug and alcohol testing. But to use this method, employers must develop a drug and alcohol testing policy that’s respectful of workers’ privacy and civil rights and makes it clear that testing is a legitimate safety measure. Creating such a policy is easier said than done. The legal standards for drug and alcohol testing are vague. One of the only ways to determine what your company can and can’t do is to look at where courts, arbitrators and labour boards (which, for simplicity’s sake, we’ll refer to collectively as “courts”) have drawn the lines on testing and structure your company’s drug and alcohol testing policy accordingly.

To make your life easier, we’ve gathered up the leading cases in this area and broken them down into seven basic rules. The “Scorecard” at the end of the article summarizes these cases. Next month, we’ll show you how to apply these rules in drafting a drug and alcohol testing policy for your company.

Defining Our Terms

Except where the context requires otherwise, when we use the terms “drugs” or “drug testing,” we’re referring to testing for both drugs and alcohol. In addition, this article addresses testing of current employees only; it doesn’t cover pre-employment testing of job applicants, which has slightly different standards.

OHSInsider: Members of www.OHSInsider.com can access drug testing guidelines published by human rights commissions, resources on drug and alcohol use in the workplace, information on the cost of drug and alcohol use at work and safety talks on drugs and alcohol.

What the Law Says

The most common argument workers use to attack drug testing is discrimination. In fact, the human rights commissions in seven jurisdictions—Fed, AB, MB, NL, NT, ON and PE—have published drug testing guidelines. The federal Canadian Human Rights Commission recently revised its drug and alcohol testing policy, which took effect on Sept. 29, 2009.

OHSInsider: Members of www.OHSInsider.com can access guidelines published by various human rights commissions, including the revised Canadian Human Rights Commission policy.

Human rights laws ban employers from discriminating against individuals with a physical or mental “disability.” The laws also ban discrimination on the basis of a “perceived” disability. And they require employers to make accommodations for workers with disabilities to the point of “undue hardship.”

Drug addiction and alcoholism are generally considered disabilities under these laws. So employers can’t treat workers who have substance abuse problems differently from other workers. In addition, treating a worker unfavourably because you think he has a drug addiction is disability discrimination even if your suspicions turn out to be wrong. Consequently, drug testing may discriminate against both drug users and non-drug users.

However, employers can justify an otherwise discriminatory practice and rule if it’s what’s called a “bona fide occupational requirement” (BFOR) designed to carry out legitimate, non-discriminatory purposes. Ensuring workplace safety is generally regarded as a legitimate and non-discriminatory purpose. So as long as a drug testing policy is motivated by a sincere, good faith concern for safety—as opposed to a pretext to cover an ulterior motive—drug testing may be permitted as a BFOR.

But to qualify as a BFOR, the safety-related practice or policy must also be “reasonably necessary” to serve the legitimate, non-discriminatory purpose. In other words, if there’s a non-discriminatory way to ensure safety, the employer can’t follow the discriminatory practice. It’s this “reasonably necessary” test that causes most of the problems when it comes to drug testing. That’s because testing isn’t reasonably necessary if there are less intrusive alternatives available.

Even if a drug testing policy satisfies the reasonably necessary test, its terms must still be consistent with the employer’s duty to accommodate. That is, the policy must address what steps the company will take to accommodate a worker who has a drug addiction or is an alcoholic. For example, a drug testing policy that requires the automatic termination of a worker who fails a drug or alcohol test without the opportunity for assessment or accommodation of the worker’s disability is likely to be considered discriminatory.

Insider Says: Although the human rights arena is the main battleground, drug testing policies can also provoke other kinds of legal disputes, including privacy complaints and allegations that the policy violates the terms of the collective agreement.

Why Court Cases Are So Critical

Court cases on drug testing are important because they show how courts decide if testing is a BFOR. Yes, different courts may analyze similar facts differently. And there are subtle differences in the human rights codes of the various jurisdictions. Still, the cases are a reliable source of guidance. Moreover, there are a handful of leading cases on drug testing that are followed across Canada.

7 Rules of Drug & Alcohol Testing

1. Random Testing of Non-Safety-Sensitive Workers Is Illegal

Testing rules differ depending on the kind of worker being tested. The courts distinguish between two groups:

1) Workers who occupy safety-sensitive positions, such as bus drivers and forklift operators; and

2) Workers who don’t.

In the landmark case of Entrop v. Imperial Oil, an Ontario court ruled that an employer can’t perform random drug and alcohol testing on workers who don’t have safety-sensitive jobs. All of the existing government drug testing guidelines follow this rule. But as you’ll see below, employers have more leeway to test workers in safety-sensitive positions.

2. Random Alcohol Testing of Workers in Safety-Sensitive Positions OK

Entrop ruled that random breathalyser testing for alcohol use is acceptable for workers in safety-sensitive positions. A positive test result is a reliable indication of impairment, the court explained, because most people don’t function well at certain blood alcohol levels. In addition, the court noted that, unlike drug tests, alcohol tests can determine whether a worker is currently impaired. Several courts have confirmed that random alcohol testing of safety-sensitive workers is acceptable, including the Ontario Court of Appeal in a May 2009 ruling [Imperial Oil Ltd. v. Communications Energy Paperworkers Union of Canada, Local 900].

3. Random Drug Testing for Safety-Sensitive Workers Is Usually Illegal

Random drug testing, however, is a different matter and is usually barred. The rationale for not allowing random drug testing comes from Entrop. As mentioned above, the court found that, unlike tests for alcohol use, drug tests don’t necessarily indicate whether the worker is impaired at the time of the test. In other words, if a worker smoked marijuana a couple of days ago, he could test positive for drugs even though the “buzz” had worn off and he wasn’t actually impaired by the time he took the test.

Exceptions: Random drug testing of workers in safety-sensitive positions has been found to be a BFOR on several occasions. For example, the Canadian Human Rights Tribunal has ruled in at least two cases that randomly drug testing drivers who drove into the US was okay because the policy was necessary to ensure compliance with US Department of Transportation regulations allowing for random drug testing of drivers in US territory [McLean Grievance].

It’s unclear whether random drug testing would also be allowed for safety-sensitive workers returning to work after a drug use suspension to ensure that rehabilitation’s working and that they’re abiding by the terms of a “last chance” agreement.

Insider Says: In 2007, an Alberta court rejected Entrop’s conclusion that drug tests don’t detect current impairment but did so in the pre-employment testing context. It ruled that a construction company could withdraw a job offer for a safety-sensitive position because the applicant tested positive for marijuana. This court concluded that because the effects of casual drug use can sometimes linger in one’s system for several days, drug testing does detect a current impairment [Alberta (Human Rights & Citizen. Commission) v. Kellogg, Brown & Root (Canada) Co.].

4. Post-Incident Testing of Safety-Sensitive Workers OK

Although random drug testing is generally illegal, it’s typically acceptable to test a worker for either drugs or alcohol after a safety incident occurs and/or when there’s “reasonable cause” to believe that the worker is impaired, provided that the worker has a safety-sensitive job. At least one federal court has taken this position [CNR v. Nat. Automobile, Aerospace, Transp. & General Workers Union of Canada)].

The human rights commissions also acknowledge the legality of post-incident/reasonable cause testing. For example, Manitoba’s drug testing guidelines say “post-incident testing, especially in safety-sensitive jobs, may be easier to justify, as may be situations where the smell of alcohol or cannabis smoke raises a reasonable suspicion of alcohol and/or drug use, or in situations where there are other reasonable grounds to believe that impairment may be present.”

But post-incident testing may cross the line if it’s too broad. For example, an Alberta arbitrator rejected a policy that subjected all workers to mandatory testing after incidents unless their supervisors had reason to believe drugs and alcohol were not involved. The policy should have been reversed, said the arbitrator. In other words, testing should have been required only if the supervisor did suspect alcohol or drug use [Communication, Energy & Paperworkers Union, Local 707 v. Suncor Energy Inc.].

5. No Post-Incident Testing of Non-Safety-Sensitive Workers

Although post-incident/reasonable cause testing of workers in safety-sensitive positions is generally permitted, it’s less clear whether it’s okay to do post-incident/reasonable cause testing of workers not in safety-sensitive positions. Theoretically, an employer could prove that such testing was reasonably necessary to ensure safety. But it would be hard to justify the necessity of such a policy for workers whose jobs don’t affect safety. For example, a court struck down a bank’s attempt to impose such testing on tellers and clerks in non-safety sensitive positions [Canadian Human Rights Commission v. Toronto-Dominion Bank].

6. Testing Workers Before Moving them to Safety-Sensitive Positions Is OK

Although workers in non-safety-sensitive positions can’t be subjected to drug and alcohol testing, they may be required to submit to such testing before being moved to positions that are safety-sensitive [Re: Canadian National Railway Co. and C.A.W. Canada].

7. Testing Policy Must Accommodate Worker

Testing policies must be consistent with the employer’s duty to accommodate, which raises two issues:

  • What, if any, accommodations employers must make before requiring workers to submit to testing in the first place; and
  • What penalties can employers impose on workers for failing (or refusing) drug tests.

One clear rule: Drug testing policies must account for each worker’s individual circumstances and characteristics. Blanket policies that treat all workers the same violate the duty to accommodate. Accordingly, “zero tolerance” policies that provide for mandatory random testing and/or automatic termination after positive drug tests are problematic. Instead, the Manitoba guidelines suggest that the reasonable accommodation duty may require an employer to:

  • Explore the possibility of transferring the worker to a less safety-sensitive position;
  • Permit—and, in fact, encourage—the worker to participate in an appropriate worker assistance program; or
  • Grant a reasonable leave of absence to allow the worker to participate in a rehabilitation program.


These seven rules aren’t set in stone. But they do represent the outlines of what has emerged as a national consensus on the legality of testing current workers for alcohol and drug use on the job.

Show Your Lawyer

Alberta (Human Rights & Citizen. Commission) v. Kellogg, Brown & Root (Canada) Co., [2007] ABCA 426 (CanLII), Dec. 28, 2007

Allied Systems (Canada) Co. v. Teamsters Local Union 938 (McLean Grievance), [2008] CanLII 13354 (ON L.A.), March 28, 2008

Canadian Human Rights Commission v. Toronto Dominion Bank, [1998] 4 F.C. (CanLII), July 23, 1998

Canadian National Railway Co. v. National Automobile, Aerospace, Transp. & General Workers Union of Canada, [2007] CanLII 43492 (ON L.A.), Oct. 16, 2007

Communications, Energy & Paperworkers Union, Local 707 v. Suncor Energy Inc., [2008] A.G.A.A. No. 55, Sept. 3, 2008

Entrop v. Imperial Oil Ltd., [2000] CanLII 16800 (ON C.A.), July 21, 2000

Imperial Oil Ltd. v. Communications Energy & Paperworkers Union of Canada Local 900, [2009] ONCA 420 (CanLII), May 22, 2009

Re: CNR Co. and C.A.W. Canada, 95 L.A.C. (4th) 341, July 18, 2000