Audi alteram partem

The principle Audi alteram partem (‘Hear the other side’) is a fundamental principle of justice or fairness, sometimes further characterised as a principle of procedural justice or fairness inasmuch as it relates directly not to the outcome of a trial or discussion but to the way in which the trial or discussion is conducted. There is also an alternative, less common, formulation of the principle which uses a passive form of the verb audire: Audiatur et altera pars (‘Let the other side be heard too’).

Audi alteram partem is perhaps most commonly cited in legal contexts – and more specifically in the context of adversarial legal systems - where it requires that all the parties in a case have the opportunity both to challenge arguments put forward by the other parties and to put forward fresh arguments of their own in support of their position. (The difficulty in meeting this condition in cases in which the accused has not been arrested and so is not present in court has led some to doubt the legitimacy of trials in absentia (i.e., trials in which the accused person is not present in court and able to defend himself or herself.))

While Audi alteram partem is conspicuously relevant in legal contexts, it is clearly applicable more widely and indeed should govern the discussion of any issue: each party to the discussion should have the opportunity both to challenge the arguments of those who disagree with them and to put forward additional arguments which support their own position.