Fourth Amendment exclusionary rule — purpose

The restrictions upon searches and seizures were obviously designed for protection against official invasion of privacy and the security of property. They are not exclusionary provisions against the admission of kinds of evidence deemed inherently unreliable or prejudicial. The exclusion in federal trials of evidence otherwise competent but gathered by federal officials in violation of the Fourth Amendment is a means for making effective the protection of privacy.

Defined by the Supreme Court in - Jones v. United States, 362 U.S. 257 (1960).