9.17 Particular Rights-Fourth Amendment-Unreasonable Search-Exception to Warrant Requirement-Emergency Aid is an exception to the Fourth Amendment's requirement for a warrant for a search or seizure. This exception allows for law enforcement to conduct a search without a warrant if there is an imminent threat of death or serious bodily harm to a person. Emergency Aid is also referred to as the "exigent circumstances" exception to the warrant requirement. This exception allows for law enforcement to enter a premise without a warrant if they have probable cause to believe that someone inside is in danger. There are two types of Emergency Aid: Emergency Assistance and Hot Pursuit. Emergency Assistance is when the police enter a premise after receiving a call from a third party, such as a neighbor or relative, who reports an emergency situation. Hot Pursuit is when the police are in pursuit of a suspect who is fleeing the scene of a crime or other dangerous situation.