The warrantless search is permitted by the courts because the fourth amendment forbids only "unreasonable" searches and seizures. Since there is a strong judicial preference for a search warrant, however, warrantless searches are not easily accepted by the courts. Once a warrantless search has been conducted, the burden is upon the government, as the party seeking to validate the search, to bring it clearly within one of the recognized exceptions created by the U.S. Supreme Court. The formally recognized exceptions are searches incident to a lawful arrest, searches based on probable cause conducted in the face of exigent circumstances, searches of motor vehicles based on probable cause, searches conducted to catalog a person's property through established inventory procedures, and searches conducted pursuant to a valid consent. Also included in exceptions are apparent searches not legally defined as searches, notably search for and seizure of property in the open fields, that has been abandoned or is in plain view.