Two wrongs make a right

Two wrongs make a right is a logical fallacy that occurs when it is assumed that if one wrong is committed, another wrong will cancel it out. Like many fallacies, it typically appears as the hidden major premise in an enthymeme&mdash;an unstated assumption which must be true for the premises to lead to the conclusion. This is an example of an informal fallacy.

It is often used as a red herring, or an attempt to change or distract from the issue. For example:
 * Speaker A: President Williams lied in his testimony to Congress. He should not do that.
 * Speaker B: But you are ignoring the fact that President Roberts lied in his Congressional testimony!

If President Roberts lied in his Congressional testimony, that does not make it acceptable for President Williams to do so as well. (At best, it means Williams is no worse than Roberts.) The tu quoque fallacy is a specific type of "two wrongs make a right". Accusing another person of not practicing what they preach, while appropriate in some situations, does not in itself invalidate an action or statement that is perceived as contradictory.

Two wrongs don't make a right
Two wrongs don't make a right is the proverb that contradicts this logical fallacy. It means that a wrongful action is not a morally appropriate way to correct or cancel a previous wrongful action.

Criticism
Common use of the term, in the realm of business ethics, has been criticized by scholar Gregory S. Kavka writing in the Journal of Business Ethics. Kavka refers back to philosophical concepts of retribution by Thomas Hobbes. He states that if something supposedly held up as a moral standard or common social rule is violated enough in society, then an individual or group within society can break that standard or rule as well since this keeps them from being unfairly disadvantaged. As well, in specific circumstances violations of social rules can be defensible if done as direct responses to other violations. For example, Kavka states that it is wrong to deprive someone of their property but it is right to take property back from a criminal who takes other's property in the first place. He also states that one should be careful not to use this ambiguity as an excuse to recklessly violate ethical rules.