Freedom from unreasonable search and seizure is a legal right that protects individuals from arbitrary intrusions by law enforcement into their privacy and property without just cause or a warrant. This principle is rooted in the Fourth Amendment of the U.S. Constitution, which establishes that citizens have the right to be secure in their persons, houses, papers, and effects against unreasonable searches. This protection is crucial for maintaining individual rights and civil liberties, ensuring that the government cannot overstep its bounds in the pursuit of law enforcement.