The United State Supreme Court has issued a ruling protecting a person's curtilage. From the Huffington Post:
The Supreme Court ruled Tuesday that police cannot bring drug-sniffing police dogs onto a suspect's property to look for evidence without first getting a warrant for a search, a decision which may limit how investigators use dogs' sensitive noses to search out drugs, explosives and other items hidden from human sight, sound and smell.This is consistent with prior precedent limiting police ability to enter property and limiting police from using means of conducting searches that fall outside normal senses (e.g., using thermal imaging devices). It doesn't appear that this will have any impact on cases involving drug dog sniffs in public areas (such as an airport, or sniffing around a vehicle stopped in a public location).
The high court split 5-4 on the decision to uphold the Florida Supreme Court's ruling throwing out evidence seized in the search of Joelis Jardines' Miami-area house. That search was based on an alert by Franky the drug dog from outside the closed front door.
Justice Antonin Scalia said a person has the Fourth Amendment right to be free from the government's gaze inside their home and in the area surrounding it, which is called the curtilage.
"The police cannot, without a warrant based on probable cause, hang around on the lawn or in the side garden, trawling for evidence and perhaps peering into the windows of the home," Justice Antonin Scalia said for the majority. "And the officers here had all four of their feet and all four of their companion's, planted firmly on that curtilage – the front porch is the classic example of an area intimately associated with the life of the home."
He was joined in his opinion by Justices Clarence Thomas, Ruth Bader Ginsburg, Sonia Sotomayor and Elena Kagan.