Legal death

Legal death is a government's official recognition that a person has died. Normally this is done by issuing a death certificate. In most cases, such a certificate is only issued either by a doctor's declaration of death or upon the identification of a corpse.

Most legal determinations of death in the developed world are made by medical professionals who pronounce death when specific criteria are met. Two categories of legal death are death determined by irreversible cessation of heartbeat and breathing (cardiopulmonary death), and death determined by irreversible cessation of functions of the brain (brain death). In the United States, each state has laws for determining these two categories of death that are modeled after the Uniform Determination of Death Act.

Cardiopulmonary criteria for death are met when a physician determines that efforts to restart a stopped heart during cardiac arrest are futile, or that no attempt should be made to restart a stopped heart, such as when there is a Do Not Resuscitate (DNR) order. In the latter case, irreversible is understood to mean that heartbeat and breathing cannot return on their own and will not be restored by medical intervention.

Brain death determinations are made in cases where heartbeat and breathing are supported by machines. Brain death is determined by there being no signs of brain function during neurological examination of a person with a beating heart. Confirmatory tests document either no blood flow to the brain, or no brain electrical activity in absence of factors known to produce reversible loss of brain function. Unlike cardiopulmonary death which sometimes involves a decision not to resuscitate the heart, brain death is a determination that the brain biologically cannot be resuscitated.

If a clinically dead person has suffered injuries so severe that resuscitation is obviously impossible, then in some jurisdictions first responders may make a legal determination of cardiopulmonary death. Such a person is said to be dead on arrival (DOA) or dead at the scene.

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