Under the Fourth Amendment to the U.S. Constitution, police can only conduct "reasonable" searches and seizures. The general rule is that before police search your home, they must prove that the search is reasonable by getting a search warrant from a neutral judge. But so many exceptions have been carved out of this rule that it looks more like the catacombs than a retaining wall. It's important to know your rights, however, since the most important exception to the rule that police need a search warrant is consent of the occupant.
Probable Cause for Warrant
The rule that police must get a search warrant before searching your home is based on the Fourth Amendment's rule that searches must be reasonable, which has been interpreted by the U.S. Supreme Court as requiring probable cause before police search a home. Officers must convince a neutral judge or magistrate that they have probable cause to believe that criminal activity is going on in the house or that they will find evidence of a crime within. They have to do more than just say the magic words "probable cause." This requirement that they spell out what evidence they have is intended to prevent abuse of the warrant process.
The type of showing the police must make to the court depends on the circumstances. Often they provide affidavits – written statements under oath – that set out information based on what they have personally seen or on knowledge given to them by private citizens or police informants. If they establish probable cause to conduct a search, the judge or magistrate issues a search warrant. Since the suspected criminal is not at this hearing, she cannot object to the evidence or dispute it in any way at that time.
Read More: Affidavit of Probable Cause
Types of Warrantless Searches
The rule notwithstanding, police often conduct searches without first getting a court warrant. The exceptions have been carved out of the Fourth Amendment over decades, as the courts find situations where a warrantless search is reasonable under the circumstances or where there is no reasonable expectation of privacy. The biggest exception to the rule that a warrant is required to search a house is consent. If the homeowner or the person living at a house agrees to a search, that search is legal. The issues raised in this kind of a search are: Did the person consenting have authority to consent and what parts of the premises did the person's consent cover? It is particularly problematic, for example, when only one of two tenants agrees to a search and the police dig through the absent roommate's room? However, courts usually rule that the police acted legally if they reasonably thought the person had authority to consent, even if it later is established that they did not.
Another exception is the plain view doctrine, which is more often used in car searches, but it can apply to a home search as well. It says that material in plain view can be seized by the police without a search warrant. The typical example is when the police pull over a car and see drugs on the seat. In a home, they might be invited into the entryway and see a dead body in plain view.
Police can also search an area without a search warrant if they are making the arrest of someone. They can, for example, look for an accomplice or a weapon in a closet, if the suspect is arrested in the living room. Stop and frisk is a similar exception. Police officers can stop someone they reasonably suspect of criminal activity. They are within their rights to search – frisk – for weapons if they think the person is armed and dangerous.
The catch-all exception to needing as search warrant is for emergencies. If the public would be in danger or criminal evidence could be lost if the police are forced to take the time to get a court warrant, they can search a home without one. For example, if they hear shrieks while passing a house, they can enter to arrest a batterer and also search the place.
Police officers generally cannot search your home without going before a judge or magistrate to get a search warrant. But many exceptions apply.
Teo Spengler earned a J.D. from U.C. Berkeley's Boalt Hall. As an Assistant Attorney General in Juneau, she practiced before the Alaska Supreme Court and the U.S. Supreme Court before opening a plaintiff's personal injury practice in San Francisco. She holds both an M.A. and an M.F.A in creative writing and enjoys writing legal blogs and articles. Her work has appeared in numerous online publications including USA Today, Legal Zoom, eHow Business, Livestrong, SF Gate, Go Banking Rates, Arizona Central, Houston Chronicle, Navy Federal Credit Union, Pearson, Quicken.com, TurboTax.com, and numerous attorney websites. Spengler splits her time between the French Basque Country and Northern California.