Which term describes the improper performance of a lawfully authorized official act?

The term that accurately describes the improper performance of a lawfully authorized official act is malfeasance. Malfeasance refers specifically to the execution of a lawful act in an unlawful or improper manner, leading to the violation of a legal duty. In the context of notarial practice, this would mean that a notary has performed their duties incorrectly while still having the legal authority to do so.

Misfeasance, while also related to the improper execution of a duty, typically involves performing an act in a negligent way that causes harm, rather than engaging in an act that is inherently wrongful. Nonfeasance, on the other hand, pertains to the failure to act when there is a duty to do so, which does not fit the description of performing an act improperly. Dereliction often refers to neglect of duties, similar to nonfeasance but more focused on willful neglect.

Understanding these distinctions is crucial for those in positions of authority, including notaries, as it impacts liability and accountability in professional conduct.