The Fourth Amendment protects us against unreasonable searches and seizures, insisting that there be verified demonstration of probable cause before a warrant will be issued. The 4th amendment applies when:
1. The citizen has manifested a subjective expectation of privacy; AND
2. That expectation is one that society (through the court) accepts as objectively reasonable.
Electronic Wiretapping (Katz v. US) and GPS tracking of a car (US v. Jones) constitutes a search and requires a warrant. For class, I made a chart of when something does (warrant needed) or doesn't (no warrant needed) constitute a search and I attached it here for everyone if they want. Mods please delete if not allowed, this was 100% made by me so no copyright issue