It is quite rare for an employee to be fired for things they do outside of the workplace. And, generally, what employees do in their private lives, as long as it remains private, has no bearing on whether or not they can be fired by their employer.
However, this does not mean getting fired for your “off hours” activities cannot happen.
An employer has the right to terminate an employee for behaviours or activities that take place outside of the workplace as long as those behaviours are contrary to the public image and reputation of the employer. In fact, many employers have a code of conduct that employees are required to abide by and which may specify that they could be fired for activities that take place outside of the workplace that brings the public image of the employer into disrepute.
This fact can take on a greater significance when the employee is well known to the public and the nature of their actions could cause harm to the employer’s “brand”. This issue has become quite a hot topic in the media recently when it became known that the CBC had fired the well known radio host Jian Ghomeshi. It was reported in various news agencies that the CBC had fired Jian Ghomeshi because certain allegations came to light and Ghomeshi stated on his Facebook page that he was fired because of the risk “of my private sex life being made public as a result of a campaign of false allegations pursued by a jilted ex girlfriend and a freelance writer.” In retaliation, Jian Ghomeshi sued the CBC for $50 million on a variety of grounds including breach of confidence and defamation.
It is important to note that even in a unionized workplace (such as the CBC) employees can be fired in cases of “just cause.” Just cause can arise out of a failure to perform one’s duties but could include something an employee does in their own time that brings the employer’s image into public disrepute.