Legal nullity refers to a situation where a legal act or agreement is considered void and has no legal effect. This can occur when the act violates laws, lacks essential elements, or is performed by parties who do not have the capacity to enter into a contract. For example, a contract signed by a minor may be deemed legally null. When an act is declared legally null, it is as if it never existed. This means that no rights or obligations arise from it, and parties cannot enforce it in a court of law. Legal nullity helps maintain the integrity of the legal system by ensuring that only valid agreements are recognized.