In general, a board of directors serves the interests of the stockholders or of the electorate, but in doing so, within the limits of the articles of incorporation or of bylaws, do so in the best judgment of the board members. Similarly, criminal conduct is not protected. Ultimately, if members of an organization disapprove of actions of a board of directions, the bylaws usually provide some mechanism for them to legitimately remove them from office. In short, the board members are responsible to the members of the organization. In an incorporated business, the stockholders are the members, not the employees, by the way.
Organizations differ greatly in their composition and nature, of course.
These comments are just a peek at a complex topic in law, but should give you the general direction of an answer to your questions. Again, if you have serious questions on critical matters to your organization, especially if they involve money, it would be a good idea to consult a competent attorney in your state. I am particularly interested in a Board of Directors of a religious congregation. The Board's authority is fully defined in the Constitution and Bylaws. The primary function is to manage the affairs of the temple-congregation.