Political Strikes

Thanks to our friends at the American Workplace Prof Blog for this story about an interesting strike in West Virginia.  Apparently, the unionized workers all stayed home for a day in protest of the employer granting permission to the National Rifle Association to come onto employer property to try to interview employees who would say bad things about Barak Obama.  This raises both the question of the right of employers to try to influence employee voting in political elections and the scope of the right to strike.  The blog links to a recent memo of the NLRB legal counsel in which he concluded that the right of US workers to strike for political (as opposed to economic reasons or in response to an employer unfair labor practice, which is allowed in the U.S.) is uncertain.
In Ontario, the right of workers to strike to protest political issues is crystal clear:  there is no right.  If workers here took a day off work to protest a political party or a law, or their employer’s behaviour, that would be an illegal strike.  See my earlier entry on the definition of ‘strike’.  Whether a Canadian employer can engage in activities–for instance, hold a captive audience meeting to persuade workers to vote Conservative or threatening employees with bad things if they don’t vote Tory–designed to influence their employee’s voting practices, on the other hand, is less clear.  
What law would that break?   It’s possible, probably even likely, that being forced at work to listen to a political message one opposes could violate a right to be free from harassment on the basis of ‘political belief’.  But in Ontario, the Human Rights Code strangely does not include political opinion as a protected ground.  (See what the United Nations’ Human Rights Committee had to say about that)
Anything else prevent employers from proselytizing about political issues at work?   How about the implied contractual right to be treated with respect and dignity at work?  (I discuss that implied term in my paper on Employer Bullying)  Possibly.  But the employee would need to sue the employer to enforce that term, and how many employees would do that?   Do you think the state should prohibit employers from political campaigning at the workplace?