Deceit and fraud shall not defend, excuse or benefit any man.

Explanation

(English-origin maxim.) No party may use fraud as a shield — deceit cannot serve as a defense, an excuse, or a foundation for any legal benefit, regardless of the circumstances.

Where this applies

• A seller who lied about a property's flood history cannot use the fraudulent sale documents as a defense when the buyer sues.
• A contractor who used substandard materials while billing for premium ones cannot claim the signed contract protects him from liability.
• An insurance company that denied a valid claim by fabricating policy exclusions cannot later use those fabricated terms as a legal shield.