Refutation is the act or process of proving that a person, statement, opinion, or argument is wrong or false. It is a common technique used in debates and arguments to introduce arguments, undermine opponents arguments, rebuild arguments, and clarify ones own arguments. Refutation can be issued against an argument retroactively from the point of reference of that argument, which is commonly referred to as a retroactive refutation). In court, a witness might offer a refutation of a suspects alibi to show that they are lying. The process of refutation can be broken down into four steps: signal, state, support, and summarize.