The police generally need to obtain a warrant based on probable cause before they can conduct a search. However, there are a number of exceptions. This guide explains the various instances when law enforcement professionals do not need a warrant to conduct a lawful search.

1) Frisk Search – In the interests of safety, a police officer is permitted to briefly frisk a person’s outer clothing for weapons. This does not mean an officer can simply search everyone in the interest of safety. The police officer needs to point out specific facts that gave them a reasonable suspicion to stop that person in the first place.

When frisking a person’s outer clothing for weapons, the police may feel other items that raise their suspicion. If the "plain feel" of the other items makes it immediately obvious to the officer that the item may be illegal, such as drugs or contraband, the officer can seize those items. The office must use the least intrusive means available to seize the items in question. This generally limits the officer to reaching into that person’s pockets.

2) Consent Searches – A consent search occurs when a person "freely and voluntarily" gives the police his consent to conduct a search. The police have no obligation to inform people that they can refuse to consent to a search. However, officers cannot coerce, trick, or intimidate someone into giving their consent to search. For example, if an officer asks: "May I come inside and look around," you can always refuse the officer unless he has a warrant to search your home. If that officer then says that he has lawful authority to search your home and that you had better let him in or your grandmother will be arrested, that search may be unlawful. It is also worth noting, that the only person who can consent to a search is the individual, or the person in control of the premises the police wish to search.

3) Plain View Doctrine – If the police are lawfully in an area, they do not need a search warrant to search for and seize evidence that is in plain view. For example, if an officer is lawfully standing inside a person’s house and sees a marijuana plant in the living room, the officer can seize the plant, and arrest the owner.

4) Search "Incident to Arrest" – Police officers do not need a warrant to search someone after they are arrested. The officer may search the person and the person’s surroundings. As a general rule, the police may search a suspect and the area within that suspect’s immediate control. Although state interpretations of the area of immediate control may vary, generally anything within the suspect’s physical reach is fair game.

5) Search of a Motor Vehicle "Incident to Arrest" – Police officers do not need a warrant to search the passenger compartment of a motor vehicle if the person they arrest was a recent occupant of that vehicle, and under two circumstances: if it is possible an the arrestee may gain access to the vehicle, or to protect evidence that may be found within the vehicle.

6) "Protective Sweep" following an Arrest – After an arrest, police officers may search for hidden accomplices by walking through a house and making brief visual inspections. However, police must justify this search with a reasonable belief that a dangerous accomplice is hiding in the residence. Provided that the protective sweep is valid, police can also seize evidence that comes into plain view during this sweep. During this type of search, the police may not look into containers that are too small to hide a person, but may search areas like closets or basements.

7) Emergency Exceptions – Police generally do not need warrants to make searches when time restraints make it impractical. Generally, when the time it would take to get a warrant would endanger public safety or risk the destruction of important evidence, a police officer may conduct a search without a warrant.

Seeking Legal Help

A criminal lawyer can help you navigate through the complex legal system and restore your privacy rights. Since the 4th Amendment is very complicated and every search is unique, a qualified attorney will be able to evaluate the legality of the search.