Both the BP oil spill in the Gulf of Mexico and the rupture of the Exxon Valdez oil tanker off the coast of Alaska in 1989 left oil-soaked birds, ruined shorelines and economic woes in their wake.
But the Valdez accident also had a wider impact on employment law in North America. According to witnesses in the court battles after the Alaska disaster, the captain of the Valdez had downed five double vodkas at waterfront bars before taking the helm. This accounts for the Alaskan catastrophe's other legacy: A push by oil companies and other industries to test employees in dangerous jobs for drugs and alcohol.
Two decades later, this push is still working its way through Canada's complex ecosystem of labour boards, human rights tribunals and courts - and somewhat unevenly, legal experts say. Courts, labour arbitrators and rights adjudicators in Alberta have been more open to drug and alcohol testing than those in other parts of Canada.
Some say a Supreme Court of Canada ruling is needed to settle the question. Meanwhile, the cases keep popping up. One of the latest pits unionized workers against the Irving Pulp and Paper Mill in Saint John. This month, the New Brunswick Court of Queen's Bench heard arguments from the company, which wants to overturn an arbitrator's ruling that struck down a policy of random alcohol testing.
"This goes back in earnest - and the timing is interesting - to the Exxon Valdez crisis. That's when companies like Exxon and in Canada, Imperial Oil [a unit of Exxon] said, 'We can't take any chances any more,'" said Richard Charney, the head of Ogilvy Renault LLP's employment-law practice who has fought a number of drug-and-alcohol testing cases on behalf of corporate clients.
"So the motivation is actually one of workplace safety and public safety."
The idea has been widely accepted in the United States for workers in safety-sensitive jobs, so the push from U.S. oil companies in Alberta is not surprising. But in Canada, companies that have brought in drug- or alcohol-testing policies have run into arguments at labour and human rights tribunals that alcohol or drug addiction is a disability, and thus testing employees - and disciplining those who are impaired on the job - is a form of discrimination.
Canadian courts have also distinguished between the more complex business of testing for illegal drugs, such as marijuana or cocaine, and the established and reliable Breathalyzer-type test for alcohol, which can immediately show if a worker is impaired. Drug tests, often involving urine analysis, take several days to show results and do not necessarily demonstrate that the employee was impaired while working.
New technology may overcome this hurdle, but so far it has not. Last year, the Ontario Court of Appeal upheld an arbitration board's decision to strike down Imperial Oil's random drug-testing policy at its refinery in Nanticoke, Ont., even though the company was using a new saliva-testing method it argued could determine with more precision whether an employee was impaired on the job.
Some testing, such as in cases when an employer has "reasonable cause" to suspect a worker in a safety-sensitive job is impaired, is generally allowed in Canada. Workers can also be tested as part of a package of conditions for returning to work after being caught for drug or alcohol abuse, Mr. Charney said.
Lawyers who act for employers point to a key case, known as John Chiasson v. Kellogg, Brown & Root (Canada) Co., as ammunition in their fight to expand the scope of employee testing. In that case, the Alberta Court of Appeal upheld the right of employers to administer drug tests to applicants for safety-sensitive posts even before they are hired, and to choose not to take on casual marijuana users. (The Supreme Court of Canada declined to hear an appeal of that ruling in 2008.)
While Alberta regulatory bodies have been more receptive to the push for employee oversight, the most-invasive testing policies - those that demand random drug and alcohol tests of all workers in safety-sensitive posts - remain difficult to defend in Canada.
For alcohol, it may be allowed in certain circumstances, Mr. Charney said. For drugs, it can be put in place if the employer can prove that an "out of control" drug culture exists among its workers.
That factor accounts for the different attitude of Alberta's courts, human rights adjudicators and labour arbitrators, said Barbara Johnston, head of Stikeman Elliott LLP's employment law group in Calgary and a veteran of high-profile testing cases.
She cites the well-documented drug and alcohol problems found in Fort McMurray, Alta., and other northern Alberta oil-boom communities, where numbers of largely young, male, well-paid oil workers are thrown together, often without family or other social support.
"When you look at the context of what's happening in Alberta, I think the cases make very clear sense," said Ms. Johnston, who represented major oil companies, including Syncrude Canada Ltd. and Imperial Oil Ltd., that intervened in the Chiasson case.
Dan Scott, of Seveny Scott Lawyers in Edmonton, who has acted for labour unions, says he believes big oil companies will continue to bring in new testing policies, even if they could face sanctions from human-rights tribunals. The reason, he suggests, is simple: The penalties they face for violating an employee's human rights pale in comparison with the millions of dollars in fines or cleanup costs after a major accident.