Just cause means that an employee has engaged in misconduct so severe that the employer can choose to immediately terminate the employee. When an employer dismisses an employee for ‘just cause’, the employee is not entitled to severance pay. In the event that the misconduct the employer relied upon to justify a ‘just cause’ dismissal did not in fact justify an immediate dismissal, an employee can pursue wrongful dismissal damages.

After-Acquired Cause Doctrine
An employer could, however, rely upon facts that support a justification for an just-cause dismissal separate from the misconduct relied upon at the times of the termination.  These facts would have to be known after the dismissal, support misconduct serious enough to warrant an immediate dismissal, and exist at the time of dismissal.
Misconduct Condoned at the Time of Dismissal
If an employer knows of the misconduct that is sufficient to justify immediate dismissal at the time, failing to do so will show the employer condoned the behaviour. In other words, the employer chose to overlook it at the time, instead of choosing to dismiss the employee. In the event that the employer tries to use such instances for after-acquired cause, the courts will not look favourable upon this for the employer. Choosing to rely upon cause known at the time will hinder the validity of the claim of after-acquired cause.
 Bad Faith Dismissal
After-acquired cause will be scrutinized by the courts in order to ensure that the employer is not trying to avoid legal obligations to provide severance. It is important that such claims are genuine; after-acquired cause runs the risk of damaging an employees reputation and in the event that it is proven the employer did so dishonestly, the employee may also be entitled to punitive damages.