What is the Fourth Amendment? The Fourth Amendment of the United States.Adopted October 13, 1857. Generally Revised November 5, 1974. The Fourth Amendment to the United States Constitution secures for every citizen of this country the right to be free from unreasonable searches and seizures. The Fourth Amendment lays out the people's right to be secure against searches, without a search warrant. View information about proposed amendments to the Minnesota constitution. The Fourth Amendment to the United States Constitution prohibits the federal government from conducting "unreasonable searches and seizures. Minnesota's constitution protects against unreasonable searches and seizures like the Fourth Amendment does. A search under Fourth Amendment occurs when a governmental employee or agent of the government violates an individual's reasonable expectation of privacy.