1. In Law enforcement, this is the principle that without warrant, based on a reasoned conclusion to prevent an very likely danger to life, limb, or property, a police officer may carry out an immediate search. 2. In Liability law, this is the principle that someone is not held to the standard of reasonable care when acting instinctively to an immediate need for help in a life-threatening situation . 3. In Medicine, this is the legal principle that, based on the reasoned belief that the patient would consent if able, when in manifest danger but incapacitated to give this informed consent, assumes a patient's consent to an emergency medical procedure.