When an agent acts in violation of his or her ethical or legal duty to the principal, should that action terminate the agent's authority to act on behalf of the principal? Why or why not?

How much obedience and loyalty does an agent-employee owe to an employer? What if the employer engages in an activity -- or requests that the employee engage in an activity -- that violates the employee's ethical standards but does not violate any public policy or law? In such a situation, does an employee's duty to abide by her or his own ethical standards override the employee's duty of loyalty to the employer?