Why did Antonin Scalia find a drug-detection dog’s sniff at a home unconstitutional in Florida v. Jardines?

In Florida v. Jardines (2013), Justice Antonin Scalia authored the majority opinion holding that the use of a drug-detection dog to sniff at a suspect’s front door constituted an unconstitutional search under the Fourth Amendment.2

Scalia’s reasoning was rooted in his commitment to originalism, which emphasizes the historical understanding of constitutional protections. He concluded that the front porch and the area immediately surrounding a home—known as the curtilage—are constitutionally protected parts of the home itself. By bringing a drug-sniffing dog onto the property to conduct an investigation, law enforcement officers had physically intruded upon a constitutionally protected area without a warrant or consent. For Scalia, this unauthorized physical invasion of private property to gather evidence violated the core protections against unreasonable searches and seizures established by the Constitution.12