The Supreme Court has never limited the Fourth Amendment's prohibition on unreasonable searches and seizures to operations conducted by the police. Rather, the Court has long spoken of the Fourth Amendment's strictures as restraints imposed upon 'governmental action' - that is, 'upon the activities of sovereign authority.' Burdeau v. McDowell, 256 U.S. 465, 475 (1921). It has held the Fourth Amendment applicable to the activities of civil as well as criminal authorities: building inspectors, see Camara v. Municipal Court, 387 U.S. 523, 528 (1967), Occupational Safety and Health Act inspectors, see Marshall v. Barlow's, Inc., 436 U.S. 307, 312 -313 (1978), and even firemen entering privately owned premises to battle a fire, see Michigan v. Tyler, 436 U.S. 499, 506 (1978), are all subject to the restraints imposed by the Fourth Amendment. As observed in Camara v. Municipal Court, supra, '[t]he basic purpose of this Amendment, as recognized in countless decisions of the Court, is to safeguard the privacy and security of individuals against arbitrary invasions by governmental officials.' 387 U.S., at 528. Because the individual's interest in privacy and personal security 'suffers whether the government's motivation is to investigate violations of criminal ...