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Search Warrants from WikiPedia:

A search warrant is a court order issued by a judge or magistrate that authorizes law enforcement to conduct a search of a person or location for evidence of a criminal offense and seize such items. All jurisdictions with a rule of law and a right to privacy put constraints on the powers of police investigators, and typically require search warrants, or an equivalent procedure, for searches within a criminal enquiry. There typically also exist exemptions for "hot pursuit": if a criminal flees the scene of a crime and the police officer follows him, the officer has the right to enter an edifice in which the criminal has sought shelter.

Conversely, in authoritarian regimes, the police typically have the right to search property and people without having to provide justifications, or without having to secure an authorization from the judiciary.

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