Twenty-seven U.S. states and the Federal government, among others, had supported Florida's argument that this use of a police dog was an acceptable form of minimally invasive warrantless search.

The Court made clear by this ruling that it considers the deployment of a police dog at the front door of a private residence to be another matter altogether.

On November 3, 2006, an anonymous, unverified tip was given to the Miami-Dade Police Department through its "crime stoppers" tip-line, indicating that the residence of Joelis Jardines was being used as a marijuana grow house.

[5]While the Miami-Dade narcotics detective was away from the scene in order to secure the search warrant, Federal DEA agents remained behind to maintain surveillance of Jardines' home.

[6] Initially, the trial court granted the defendant's motion to suppress evidence that was obtained from his home, citing the authority of State of Florida v.

[8] Summarizing their reasoning, the DCA stated: We do so because, first, a canine sniff is not a Fourth Amendment search; second, the officer and the dog were lawfully present at the defendant's front door; and third, the evidence seized would inevitably have been discovered.

[13] In a 5–2 decision rendered on April 14, 2011, Florida's Supreme Court sided with Jardines, saying: "We have said that the Fourth Amendment draws 'a firm line at the entrance to the house.'

Therefore, we conclude that the ... exposure of respondent's luggage, which was located in a public place, to a trained canine – did not constitute a "search" within the meaning of the Fourth Amendment.

[20]In the third case, Illinois v. Caballes (2005),[21] the Supreme Court ruled that a minimally intrusive warrantless dog sniff of a vehicle was permissible at routine traffic stops.

The Caballes Court said that: A dog sniff conducted during a concededly lawful traffic stop that reveals no information other than the location of a substance that no individual has any right to possess does not violate the Fourth Amendment.

[22]This conclusion, which upheld the constitutionality of certain minimally intrusive warrantless searches, was based on the premise that: Consistent with previous rulings, the Court again maintained that an individual has no reasonable expectation of privacy while on public property, and that a dog sniff, being sui generis, revealed only information about contraband which nobody has the right to possess.

[23] In Jacobsen, the Supreme Court answered the question of whether police could temporarily seize and inspect a package without probable cause, because it had been damaged in transit and had white powder spilling from it.

Here, as in Place, the likelihood that official conduct of the kind disclosed by the record will actually compromise any legitimate interest in privacy seems much too remote to characterize the testing as a search subject to the Fourth Amendment.

A dog sniff conducted during a concededly lawful traffic stop that reveals no information other than the location of a substance that no individual has any right to possess does not violate the Fourth Amendment.

[27]In its analysis of the above cases, the Florida Supreme Court drew a clear distinction with respect to a dog sniff test that was not conducted against a vehicle, but against a private residence: Significantly, all the sniff and field tests in the above cases were conducted in a minimally intrusive manner upon objects—luggage at an airport in Place, vehicles on the roadside in Edmond and Caballes, and a package in transit in Jacobsen—that warrant no special protection under the Fourth Amendment.

... Further, and more important, under the particular circumstances of each of the above cases, the tests were not susceptible to being employed in a discriminatory or arbitrary manner ... and there was no evidence of overbearing or harassing government conduct.

Although police generally may initiate a "knock and talk" encounter at the front door of a private residence without any prior showing of wrongdoing, ... a dog "sniff test" is a qualitatively different matter.

Thus, if government agents can conduct a dog "sniff test" at a private residence without any prior evidentiary showing of wrongdoing, there is simply nothing to prevent the agents from applying the procedure in an arbitrary or discriminatory manner, or based on whim and fancy, at the home of any citizen.In a separate concurrence, joined by two justices from the Florida Supreme Court, Judge Lewis went a step further: We as Americans have an unwavering expectation that there will not be someone, or something, sniffing into every crack, crevice, window, or chimney of our homes.

This protected interest of the expectation of privacy will be obliterated if a single individual, manipulating an animal, is permitted to make the final determination as to whether the government should enter into a private residence based upon an unverified, uncorroborated, anonymous tip.

To sanction and approve turning the "dogs loose" on the homes of Florida citizens is the antithesis of freedom of private property and the expectation of privacy as we have known it and contrary to who we are as a free people.

Scientific research establishes that instead of smelling cocaine, drug-detection dogs alert to methyl benzoate – an odor shared by snapdragons, petunias, perfumes and food additives.

Instead of smelling MDMA ("Ecstasy"), drug-detection dogs alert to piperonal – an odor shared by soap, perfume, food additives and even lice repellant.

(citation omitted)In their petitioner's brief, the State of Florida argues that the lower court improperly relied on Kyllo and erred in equating the dog sniff with a search, in that:[16]

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.

"[43] This conclusion is consistent with the Court's early Fourth Amendment jurisprudence, which until the latter half of the 20th century was tied to trespass under common law.

"[50] The Court acknowledged that a doorbell or knocker is typically treated as an invitation, or license, to the public to approach the front door of the home to deliver mail, sell goods, solicit for charities, etc.

However: This implicit license typically permits the visitor to approach the home by the front path, knock promptly, wait briefly to be received, and then (absent invitation to linger longer) leave.

Complying with the terms of that traditional invitation does not require fine-grained legal knowledge; it is generally managed without incident by the Nation's Girl Scouts and trick-or-treaters.

[51]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 common law.

The Court concluded that bringing a police dog into the home's curtilage to perform a forensic exploration for incriminating evidence was therefore an unreasonable search, absent a warrant.