Justices, in a 5-3 decision, said that police did not have the authority to enter and search the home of a small town Georgia lawyer even though the man's wife invited them in.
The officers, who did not have a search warrant, found evidence of illegal drugs.
The Supreme Court has never ruled on whether the Constitution's ban on unreasonable searches covers a scenario when one home occupant wants to allow a search and another occupant does not.
The ruling by Justice David H. Souter stopped short of fully answering that question — saying only that in the Georgia case it was clear that Scott Fitz Randolph was at the door and objected to the officer's entry.
CBS News legal analyst Andrew Cohen called it a "wishy-washy decision."
"The majority says that as long as one resident inside the home objects to a search that objection has to be taken seriously by the police," Cohen said. "But the majority also says that in some cases that objection by the resident won't be enough to preclude a search."
In his first written dissent, Chief Justice John Roberts said that "the end result is a complete lack of practical guidance for the police in the field, let alone for the lower courts."
The case fractured a court that has shown surprising unanimity in the five months since Roberts became chief justice. Justices swapped barbs in their writings, with Souter calling Roberts' view a "red herring."
Justices Antonin Scalia and Clarence Thomas filed separate dissents, and Justice John Paul Stevens and Stephen Breyer wrote their own opinions to explain their votes in favor of the man whose home was searched.