While the media's attention is squarely focused on the issue of gay marriage, the United States Supreme Court has released its "easy" decision in Florida v. Jardines regarding whether the police can bring a drug dog to your front door for a sniff without a search warrant. As SCOTUSblog explains:
In an opinion written by Justice Scalia, the Court affirmed the Florida Supreme Court. The Court held a dog sniff at the front door of a house where the police suspected drugs were being grown constitutes a search for purposes of the Fourth Amendment. Justice Kagan filed a concurrence joined by Justices Ginsburg and Sotomayor. Justice Alito filed a dissent joined by the Chief Justice, and Justices Kennedy and Breyer.
Note that the opinion was written by Justice Scalia and joined by Justice Thomas and Justice Ginsburg. We saw these same three join in the majority in the Kyllo case from 2001 which held that police pointing a thermal imaging device at a home was also a search for 4th Amendment purposes. Property rights cases are interesting at the Supreme Court level because you will often find Justices labeled as "liberal" or "conservative" joining forces. It's not odd to see "liberals" siding with the government nor to see "conservatives" siding with homeowners.
The first question the court has to answer is whether bringing a dog to a homeowner's door is a search. If it is, then case closed, because these particular officers were not authorized to conduct a search. If it is not a search, more questions would follow.
From the opinion:
[W]hen it comes to the Fourth Amendment, the home is first among equals. At the Amendment’s “very core” stands “the right of a man to retreat into his own home and there be free from unreasonable governmental intrusion.” This right would be of little practical value if the State’s agents could stand in a home’s porch or side garden and trawl for evidence with impunity; the right to retreat would be significantly diminished if the police could enter a man’s property to observe his repose from just outside the front window.
We therefore regard the area “immediately surrounding and associated with the home”—what our cases call the curtilage—as “part of the home itself for Fourth Amendment purposes.” That principle has ancient and durable roots. Just as the distinction between the home and the open fields is “as old as the common law,” so too is the identity of home and what Blackstone called the “curtilage or homestall,” for the “house protects and privileges all its branches and appurtenants.” This area around the home is “intimately linked to the home, both physically and psychologically,” and is where “privacy expectations are most heightened.”
While the boundaries of the curtilage are generally “clearly marked,” the “conception defining the curtilage” is at any rate familiar enough that it is “easily understood from our daily experience.” Here there is no doubt that the officers entered it: The front porch is the classic exemplar of an area adjacent to the home and “to which the activity of home life extends.”
Because the Court holds that bringing a drug dog to the front door of a home is a search, they avoid having to answer other questions about whether a dog's behavior at the front door gives officers grounds for an immediate exigent circumstances search, a search warrant based on the dog's behavior, or nothing at all. Those questions will have to wait for a later day, for as Justice Scalia writes, "One virtue of the Fourth Amendment’s property-rights baseline is that it keeps easy cases easy."