What is the term for performing a lawful act in an illegal or improper manner?

The term for performing a lawful act in an illegal or improper manner is misfeasance. This concept refers to the execution of a legal action that is carried out incorrectly or in a harmful manner, leading to injury or damage. For example, if a healthcare professional administers a medication, which is a lawful act, but does so in a negligent way that causes harm to a patient, it would be considered misfeasance.

This term highlights the distinction between simply failing to act (nonfeasance) and performing an act but inappropriately or carelessly. Misfeasance indicates that the action itself was permitted by law; however, the way it was executed caused harm, thus breaching a duty of care. Understanding this concept is crucial in the context of medical malpractice, as professionals can be held liable for the improper execution of their duties, even if those duties are generally lawful.