Because of the Fourth Amendment’s protections, courts presume that searches and seizures inside a home without a warrant are unreasonable. And evidence police officers obtain after illegally entering a home is inadmissible in court.
But if an occupant consents to the police searching a home, the search may be valid. It’s a relatively easy question when the owner of a home agrees to the police searching the premises—the search is, in all likelihood, legal.
Even occupants who have less than full rights over the premises can, through consent, provide legal justification for officers searching parts of the house. For example, a roommate can give consent that allows the police to search her room, the living room, and the kitchen. But since she doesn’t have access to or control over her roommate’s separate bedroom, she can’t provide proper authorization for the police to search it. (For more, see Where the Police Can Look When Your Roommate Consents to a Search.)
So, what happens when a houseguest tells the cops that they can search a home?
If the owner of a home authorizes a third party to allow the police to look around, that third party’s consent will justify a search. And a person who doesn’t live in a home but who uses and has joint access to or control over parts of it can authorize the police to search those parts.
But someone who is a mere guest generally doesn’t have authority to let the police snoop around. The question is whether police officers reasonably believe that someone who provides consent has normal access to and use of the parts of the house to be searched. Even if that person turns out to be a guest without any such access or control, the officers’ reasonable but mistaken belief otherwise legitimizes a search.
For more on searches pursuant to a guest’s agreement, including those where the primary residents are present, see Ignorance Isn’t Bliss: When Police Search a Home With Only a Guest’s Consent.