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. This case follows closely behind Florida v. Harris, where the Court in February ruled that an alert from a well-trained narcotics detection dog certified to detect illegal contraband is sufficient to establish probable cause for the search of a vehicle, reversing the Florida Supreme Court. The decision in that case was unanimous.
At trial, Jardines moved to suppress the marijuana plants on the ground that the canine investigation was an unreasonable search. The trial court granted the motion, and the Florida Third District Court of Appeal reversed. On a petition for discretionary review, the Florida Supreme Court quashed the decision of the Third District Court of Appeal and approved the trial court's decision to suppress, holding that the use of the trained narcotics dog to investigate Jardines' home was a Fourth Amendment search unsupported by probable cause, rendering invalid the warrant based upon information gathered in that search.
Justice Scalia's majority opinion, joined by Justices Kagan, Thomas, Ginsburg and Sotomayor, did not focus on the right to privacy, which is implicated by most modern-day Fourth Amendment cases. Rather, the decision hinged on the basis of a citizen's property rights. It followed the 2012 precedent from United States v. Jones, that when police physically intrude on persons, houses, papers, or effects for the purpose of obtaining information, "a 'search' within the original meaning of the Fourth Amendment" has "undoubtedly occurred." The Court held that the curtilage may not be used by a canine officer to sniff for marijuana and relied on long-standing rules regarding cartilage. Scalia used the analogies of a "visitor exploring the front path with a metal detector", or allowing police to "peer into the house through binoculars with impunity" to illustrate such activities that are not implicitly licensed by the homeowner, which would constitute a trespass under. Scalia also determined that it was unnecessary to address whether or not Jardines' privacy was impacted.
Justice Kagan, joined by Justices Ginsburg and Sotomayor, added to the binoculars example to argue further that both property and privacy rights are equally implicated. "A stranger comes to the front door of your home carrying super-high-powered binoculars. He doesn't knock or say hello. Instead, he stands on the porch and uses the binoculars to peer through your windows, into your home's furthest corners. ... Has your 'visitor' trespassed on your property, exceeding the license you have granted to members of the public...? Yes, he has. And has he also invaded your 'reasonable expectation of privacy'...? Yes, of course, he has done that too. That case is this case in every way that matters." The concurring opinion stated the controlling case supporting this position was Kyllo v. United States, the previously decided case involving the use of a thermal imaging device. 
The dissent found no support in the common law for the majority’s conclusion that the police conduct here constituted a trespass. The dissent pointed out that the majority acknowledged that the public, including the police, have license to approach the front door. The dissenters also did not view the dog sniff as invading any reasonable expectation of privacy given that one can expect that odors will drift outside of a house and, possibly, into public areas where there is no question a dog could sniff for evidence of drugs without constituting a search.
Justice’s Kagan’s concurring opinion seems to be more attenuated with the reality of what Jardines is all about. Does a person have a reasonable expectation of privacy inside of their home? That is essentially a no brainer and is backed by case precedent. A canine dog is a tool utilized by the police to obtain probable cause to search an area. The issue at heart is where may the canine dog do this? The answer is governed by the answer to whether the searched item has a reasonable expectation of privacy where the canine dog is sniffing, like a vehicle on a public highway. The home is private property where there is a reasonable expectation that the government should not simply be able to approach your home and use an extrasensory tool without probable cause.
Diana CoboJunior Blog Editor, Criminal Law Brief
 Florida v. Jardines, No. 11-564, 2013 BL 79684 (U.S. Mar. 26, 2013); see link http://www2.bloomberglaw.com/desktop/public/document/FLORIDA_v_JARDINES_No_11564_2013_BL_79684_US_Mar_26_2013_Court_Op
 Florida v. Harris, No. 11-817, 2013 BL 42777 (U.S. Feb. 19, 2013); see link http://www2.bloomberglaw.com/desktop/public/document/Florida_v_Harris_No_11817_2013_BL_41063_US_Feb_19_2013_Court_Opin/1
 Jardines v. State of Florida, 73 So. 3d 34 (Fla. 2011); see link http://www2.bloomberglaw.com/desktop/public/document/Jardines_v_State_73_So_3d_34_Fla_2011_Court_Opinion
 Kyllo v. United States, 533 U.S. 27 (2001); see link: http://scholar.google.com/scholar_case?case=15840045591115721227&q=kyllo+v.+united+states&hl=en&as_sdt=2,21&as_vis=1