It can happen. You are injured at work. The employer is upset. The employer knows his insurance rates will go up. As a retaliation for the injury he “fires” you. First, unless you are a union or government worker, the employer normally has the right to fire his/her employees for no reason at all. This is called the “employee at will” doctrine. Most employers are smart enough not to fire someone just because the worker suffered an injury on the job. However, this does happen.