The fourth amendment to the constitution guarantees the right to be free from unreasonable searches and seizures, and is often argued as protecting our right to privacy.
Amendment IV
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.