Employers are prohibited from discriminating against workers based on certain prohibited grounds. Prohibited grounds include physical or mental disability. Thus, if an employer dismisses an employee because of a real illness, the employer generally commits a prima facie breach of human rights law.
One important exception/defence that is recognized by both the courts and the BC Human Rights Tribunal is “frustration” of contract. In a nutshell, the legal doctrine of “frustration” says that if your illness causes you to be off work for an extremely long period of time – unexpected by either party – and there is no prognosis for a definite return to work, at some point the employment contract can become frustrated. The ramifications to the employee are severe – there is no notice/severance owing to an employee whose contract becomes frustrated. How long it takes for a contract to become frustrated varies from case to case.
As a general premise and precaution, if you are involved in a case involving a work absence of more than a year due to illness, you should seek legal advice on frustration of contract.