Ratified December 15, 1791
Protects against "unreasonable searches and seizures" and requires that warrants be specific and based on probable cause, sworn under oath. This is the constitutional foundation for most modern rules about police searches, wiretaps, and digital privacy.
The right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures, shall not be violated, and no Warrants shall issue, but upon probable cause, supported by Oath or affirmation, and particularly describing the place to be searched, and the persons or things to be seized.