Be careful about the people with whom you choose to share a home. If they invite the police inside, you’ve lost your rights to be protected from warrantless searches—even if you object.

In a disturbing and misguided decision, the Supreme Court has ruled that police may enter and search your home against your wishes, and without a warrant, as long as someone else you live with gives them approval to do so. In a 6-3 decision, with all three female Justices dissenting, the court overruled a 2006 holding that law enforcement could not conduct a warrantless search if occupants of a home disagreed about whether to allow it.

NPR reports:

The decision came in the case of Walter Fernandez, suspected in a gang robbery and assault. Police, looking for the robber, entered an apartment house and heard screaming from one apartment. When they knocked on the door, Roxanne Rojas answered.

She appeared to be crying, had a bump on her nose and blood on her shirt. She agreed to let the police search the apartment, but at that point Fernandez stepped from the back of the apartment wearing only boxer shorts. He told police they had no right to search the apartment; he was refusing consent.

Police, suspecting domestic violence, then arrested Fernandez and took him away. An hour later, they returned, without a warrant, and got Rojas' consent for the search in writing. They found a sawed-off shotgun, ammunition, gang paraphernalia, and clothing that matched the description of the robber's clothes.

Fernandez was convicted but then appealed, challenging the warrantless search that served as the basis for his robbery charge. On Tuesday, the Supreme Court denied his appeal. Citing the rights of domestic violence survivors, Justice Alito, writing for the majority, ruled that "[d]enying someone in Rojas' position the right to allow the police to enter her home would also show disrespect for her independence."

But the three female justices, all of whom dissented, disagreed. Nothing in the law prevents cops from entering a home to remove a suspected abuser, they said. The issue in Fernandez was about whether or not police could conduct a warrantless search, not conduct an arrest.

"The specter of domestic abuse hardly necessitates the diminution of the Fourth Amendment rights at stake here," they wrote.

While this is a serious blow to Fourth Amendment protections from unwarranted searches of our most private spheres—our homes—we shouldn’t give up all hope. State high courts may very well rule that state constitutions protect us from these kinds of shady, backdoor searches.

But until then, here's some practical advice: pick your housemates carefully, and share this decision with them. Make it clear that if one of you grants police or federal agents access to search part of the home, this person is in effect giving away every other resident's right to privacy, too.