Alberta's oil patch is carefully looking at a court ruling that said firing an employee for failing a drug test was discrimination.

The ruling handed down in May by Court of Queen's Bench Justice Sheilah Martin ignores safety issues in the oil patch, said Murray Sunstrum, a vice-president at Enform, a petroleum safety and training association.

The Court ruled that construction company Kellogg, Brown and Root discriminated against John Chiasson when he was fired for failing a drug test taken before he was hired in 2002.

Sunstrum called the ruling a profound disappointment for the industry.

"It ignores the human rights of the other workers on the worksite, particularly because we do so much work as crew work," he said.

"[The ruling also] doesn't recognize that employers have an obligation to provide a safe workplace and in fact stands as an impediment to providing that."

Sunstrum said the province is aware of the problem with drug use in the oil patch and it should be working with the industry to create clear guidelines on employee drug testing in Alberta.

Human Rights Commission rejected complaint

Chiasson was terminated nine days after starting a job as a receiving inspector at Syncrude's plant north of Fort McMurray in 2002.

He complained to the Alberta Human Rights Commission, arguing that his cannabis use is recreational, outside of work, and not the result of an addiction, and that the pre-employment drug test was discriminatory. The commission ruled against Chiasson.

The Court of Queen's Bench ruling overturned that finding, saying he must be treated as an addict and therefore was protected from being fired under human rights law.

Limits company power

That limits the power of companies to choose who they hire, said Calgary labour lawyer Tina Giesbrecht.

"It is saying somebody testing positive for drugs does not mean that you can discriminate against them by not hiring them or by not continuing their employment," she said.

Pre-employment drug testing is becoming common in the oil patch, so the ruling has caught the attention of lawyers and employers.

This case also veered from the traditional distinction between a casual drug user and someone with an addiction.