WASHINGTON – Franky found drugs in Florida. He’s a dog, so he left the constitutional questions to others.

But Franky’s work in Miami and another drug-sniffing dog’s diligence in Liberty County, Fla., will draw the Supreme Court’s attention this week. Not for the first time, justices must figure out when a canine sniff is a search, with all the constitutional consequences that implies.

“The Fourth Amendment says no unreasonable search and seizures,” said Nicholas Quinn Rosenkranz, a professor at the Georgetown University Law Center, “so is that a search that triggers the Fourth Amendment inquiry?”