Every presumption of the law must be in aid of justice.

Explanation

(English-origin maxim.) Legal presumptions exist to advance justice, not to defeat it — a presumption that operates to deprive a man of his recognized rights or to shield wrongdoing perverts its own purpose and must yield to the truth of the matter.

Where this applies

• When a deed is ambiguous, the court presumes it was intended to convey a valid title, because legal presumptions must serve justice, not defeat it.
• A court presumes that a government official acted within his authority unless proven otherwise, because the presumption of regularity aids justice.
• When evidence is equally balanced, the court applies the presumption of innocence in favor of the defendant, because every legal presumption must advance a just outcome.