When a clothing retailer that employed a man who posted negative comments about the death of Amanda Todd found out about his online activities, it didn't hesitate to take action.

The man was fired from his job at a London, Ont., outlet of Mr. Big and Tall, with the company CEO saying the firm was taking the action it felt was appropriate.

'It's a hard question to answer.'—James Heeney

While the company moved quickly, it's a case that highlights a tricky area where the law and the rapidly changing world of social media cross.

It also prompts the question of just when is it legal to dismiss someone because of something he or she posts online."It's a hard question to answer," says James Heeney, a Toronto employment lawyer with the firm Robinson Heeney LLP. "It often depends on the individual you're talking about."

But broadly speaking, there are two paths such "revelation of character" cases can go down, he says.

One is the conduct of an employee outside work that has a direct impact on the company itself. For example, an employee who writes a blog that includes negative or disparaging comments about the boss, co-workers and others in the workplace.

The other involves cases where someone's behaviour is "just simply inconsistent with the values or the goals of the corporation as a whole," says Heeney.

Such instances can become grounds for legal dismissal.

Depends on the circumstances

Underlying cases like these are some basic tenets of employment law in Canada.

"A non-unionized employee can be terminated with what the courts call reasonable notice for any reason other than a violation of human rights law," says Claire Mummé, Schulich Fellow at the Schulich School of Law at Dalhousie University in Halifax.

"So, in this instance, if this employee was given reasonable notice of termination there wouldn't need to be a cause for dismissal."

If there isn't any notice, then the question becomes whether there was cause for the firing.

"Whether or not there was cause for dismissal in regards to online postings will likely depend on where the postings were," Mummé says, pointing to issues such as how closely related to the workplace it was and whether there was a reasonable expectation of privacy there.

Also considered would be issues such as whether the comments reflect insubordination or disloyalty to the employer, are a violation of a workplace policy that the employee knew about, or whether the postings could harm the employer's reputation.

The individual facts of the case would play a significant role.

In a unionized environment, workplace rights and obligations are determined by the collective bargaining agreement, rather than common or statuatory law, she adds.

Notice isn't enough

"Most collective bargaining agreements specify that you can only be dismissed for cause — notice is not sufficient —  and tend to have greater procedural rights about what types of behaviour constitute cause," she added, pointing to the case of a Canada Post worker fired for Facebook postings that contained mocking and derogatory comments about her supervisors and the corporation.

But what if someone makes a comment online that has nothing to do with work, but which might be something the boss just doesn't like? If the boss discovers that comment, could you be fired?

In the non-unionized workplace, the answer is yes.

"The example I often use when I teach this material in class is to say if an employee posts on their Facebook page that they're a Toronto Maple Leafs fan, and the boss is an Ottawa Senators fan, they can be fired for that," says David Doorey, associate professor of labour and employment law at York University's school of human resource management in Toronto.

"The only issue is how much notice are they entitled to."

As with so much else in life, however, there are exceptions.

"In a non-unionized environment the employer can fire someone for whatever reason they like provided it doesn't violate [a] statute," says Doorey.

"For example if the employee put on their Facebook page that they're going to church this weekend, and the employer fires them for that, that would be a problem because that would be a violation of human rights statutes."

In a private workplace, there is no right to free expression, he says.

Employer's business

"The vast majority of people believe that what they say outside of the workplace is none of the employer's business. But that's not true. The employer can always fire you for whatever you say. The only issue again is whether you're entitled to some sort of notice before you're fired."

The firing could come without notice if the employee "committed a serious wrong that could harm the economic interest of the employer," he says.

In the unionized environment, however, there needs to be just cause for dismissal and contracts set this out.

Heeney says both employers and employees need to be mindful that the closer the link between online conduct and the employer, the more likely the employer is to act on that behaviour. And in light of that, there's some advice his legal firm can offer people:

"If you have something negative to say about your work or a co-worker, that's the type of thing that you share privately with your family when you're at home. You don't post it on Facebook or Twitter because you have to be mindful that if you were the person that had those comments made about them, you would be humiliated to continue to work with that person. "

"You just need to be mindful that the internet has a great power, but ultimately you have to use discretion in exercising your right, because in this market you don't want to lose your job."