The Fourth Amendment to the Constitution prohibits unreasonable searches and seizures by the government, in the state of New York and across the country. Generally, this means that police and other agents of the state are not allowed to search or seize the person or property of an individual without a warrant. The Fourth Amendment also briefly sets forth the requirements for a search warrant: probable cause supported by oath and a particular description of the place to be searched and the property or persons to be seized.
Who can issue a warrant?
The search warrant process is more-or-less uniform throughout the United States. Warrants are not issued by police; they are issued by a judge or magistrate. The point of this requirement is to prevent illegal searches and seizures by having an independent arbiter, rather than a law enforcement officer, makes the decision whether or not the evidence presented supports a finding of probable cause.
Showing of probable cause
The definition of probable cause is not in the Fourth Amendment nor is it in a federal statute. Rather, it is a judicial construct. The application for the issuance of a search warrant must state facts sufficient for the judge or magistrate to make a probable cause determination. The issuance of a warrant will be upheld so long as the magistrate had a substantial basis to find probable cause.
Particularity in search warrants
The Fourth Amendments requirement of particularity prevents general searches, i.e., the state is prohibited from just searching a person’s home in order to see if they are breaking any laws. Instead, law enforcement agencies must particularly state what they are looking for and where they will look. If the search warrant is for a stolen car, for example, the police cannot go through the suspect’s bedroom closet. A stolen car could not be there. The Fourth Amendment is designed to prevent unjustified intrusions into people’s private lives. If a search is challenged, the evidence resulting therefrom may be inadmissible at trial.