Written in the Constitution
The right of the people to be secure in their person, houses, papers and effects against unreasonable searches and seizures shall not be violated, and no warrants shall be issued, but upon probable cause, supported by oath.
Amendment in my words
The police are not allowed to search your house with out a warrant. If the police still search they cant charge you with anything.
Supreme Court Case
Briefly Explain: Let the police do drug test on students at anytime they want.
Court Decision: They ruled that bodily searches of students are an invasion of their privacy.