Congress has recognized that sometimes this power can be abused by managers who retaliate if they don't like something that employee has said or done.

This week, the US Supreme Court will hear oral arguments in two cases examining how, when – or even if – employees can fight back against such abuses of power. On Tuesday, the high court will examine whether a US postal worker can claim retaliation in a lawsuit under the Age Discrimination in Employment Act because she says her supervisor refused to let her return to her old job because he didn't like her personally. Instead, he hired a younger, less experienced worker.

On Wednesday, the justices will hear the case of a former assistant manager at a Cracker Barrel restaurant who alleges he was fired in retaliation for his repeated complaints about racial prejudice by his supervisor.

In both cases the laws cited do not explicitly authorize legal action in response to an act of retaliation. Lawyers for the employees say retaliation is a particularly virulent form of illegal discrimination and thus falls within the scope of the US's civil rights laws even when those laws don't specifically mention retaliation.

Lawyers for companies and supervisors counter that if Congress wanted to authorize lawsuits to punish acts of retaliation, it would have written it into each statute.