The determination and pronouncement of when a person has died has medical, ethical, and legal implications. Laws vary from state to state, and death is usually defined in a state’s statutes.

Definitions and terminology may vary from state to state but generally a person is dead when, according to ordinary standards of medical practice, there is irreversible cessation of the person's spontaneous respiratory and circulatory functions. If artificial means of support preclude a determination that a person's spontaneous respiratory and circulatory functions have ceased, the person is dead when, in the announced opinion of a physician, according to ordinary standards of medical practice, there is irreversible cessation of all spontaneous brain function.

Death occurs when the relevant functions cease. But a formal pronouncement of death is not a legal determination of the cause, manner, or time of death.

In Hawaii, the determination of death is governed by state statutes that align with the medical and ethical standards commonly accepted across the United States. According to Hawaii Revised Statutes §327C-1, a person is legally recognized as dead if there is an irreversible cessation of circulatory and respiratory functions, or if there is an irreversible cessation of all functions of the entire brain, including the brain stem, as determined by a physician. The statute specifies that the determination of death must be made in accordance with accepted medical standards. The pronouncement of death itself is a medical action that signifies that these functions have ceased, but it does not establish the legal cause, manner, or exact time of death. These latter determinations are typically made through a death investigation, often involving a coroner or medical examiner, depending on the circumstances surrounding the death.