Well, the noble defenders of the Constitution on the US Supreme Court need to head back to law school, because they clearly don't understand that whole pesky "shall not be violated" part in the 4th Amendment:
The right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures, shall not be violated, and no Warrants shall issue, but upon probable cause, supported by Oath or affirmation, and particularly describing the place to be searched, and the persons or things to be seized.
On Tuesday, a majority of the justices decided that a warrant is no longer needed to search your home if one of the residents of the home says that it's okay with them, as long as the person who disagrees and refuses entrance to the police is arrested. Clearly, if the cops want in badly enough, they can create find a reason to arrest the person who is refusing them entrance based on his or her 4th Amendment right to do so. Militia News provided some background on the decision:
In 2009, Walter Fernandez, a Los Angeles resident, was arrested and removed from his residence. During the incident, Fernandez refused police entry into his home as a violation of his 4th Amendment rights because the officers did not have a warrant.
Once Fernandez was in custody, the police returned to his residence and searched anyway. Their findings became evidence in the prosecutor's case against Fernandez.
Based on the findings and previous rulings in Fernandez' case, the USSC ruled that the police had a lawful right to search his home and Fernandez was in the wrong in having prevented that police from doing so during his arrest.
Justice Samuel Alito, author of the decision, explained that: "A warrantless consent search is reasonable and thus consistent with the 4th Amendment irrespective of the availability of a warrant. Even with modern technological advances, the warrant procedure imposes burdens on the officers who wish to search [and] the magistrate who must review the warrant application."
Ginsberg pointed out: "Instead of adhering to the warrant requirement, today's decision tells the police they may dodge it." (source)
Judge Andrew Napolitano feels that there is great potential for abuse and he told Fox and Friends why he was so displeased with the decision.