I'll restrict my answer more to the mandate of workplace safety, if I may.
I think the focus on a safety sensitive position and more information and more potential testing is again to focus on the welfare and safety of the worker. Employers generally are neutral on the politics or the legality of any substance, including cannabis. What they need and want to know is that workers will come to work, they'll be sober, they'll be able to work safely, and they won't hurt themselves or anyone else or the public. That's the key focus of these suggested amendments to the Canada Labour Code.
The other aspect of your question I think is a little broader than my mandate. I think there isn't a great deal of stigma out there, whether you accept this or not, for having a medical authorization for marijuana. It's been available since 2000. It's funded by workers' compensation boards when people need treatment for a workplace-related injury. In fact, it's talked about freely and openly.
The legality-illegality issue is not the primary focus of worries and concerns. It's the effect it's going to have on safety in the workplace and the fact that it's only the employer who gets blamed when there's an accident if somebody's impaired.