In the U.S., police officers are allowed limited searches of vehicles and clothing so long as they have cause to believe that the search will reveal drugs or weapons. Also, if they are pursuing a suspect who flees the scene of a crime and takes shelter in a house or other building, they are allowed to enter the building and perform a search of its contents. A search warrant is therefore necessary to perform a search of a person’s home or other personal dwelling or workplace. The warrant can only be obtained if the officer investigating a case has probably cause to believe that such a search will uncover enough evidence to convince a judge or jury that conviction is necessary for a suspect.
Search warrants are given out on the premise that the evidence already collected by officers and investigators is not enough for a conviction but that it belies such evidence elsewhere. Warrants such as these are specific; they must state clearly what is being searched for and where it is being looked for. To search another room, a vehicle or a garage will require another permit and so the investigators must be very certain about what they are looking for and where it might be.
The exceptions to the search warrant rule, aside from those stated above, are when an emergency situation has arisen and it is believed that the public is in danger. If a suspect has agreed to let the police come in and perform a search then a warrant is not necessary; also if a police officer is in plain view of weapons or contraband while being in a normal position (at the door) they are required to confiscate it. When an officer makes an arrest for any reason, it is protocol to search the rooms in which the suspect would have had access and also any vehicles in which he or she has been in recently. This is to ensure that no evidence has been missed and also to rid the area of any other suspects that may be hiding until the police leave.
Essentially, police are not allowed to search your home unless they have a warrant, and they cannot obtain a warrant unless they have real reason to think that you are hiding something illegal or pertaining directly to a criminal charge. If they come to your door without a warrant, you are entitled to turn them away; this does not guarantee that they will not return with the proper documentation, but this is your right nevertheless. When it comes to your possessions, you are entitled to keep your privacy until the authorities come up with a solid reason to enter your home and find what they are looking for.
Knowing where your rights stand on searches may not win you any friends on the police force, but when you don’t feel like opening up your own space to scrutiny by strangers who think you are in the wrong, it can’t hurt!