The Supreme Court on Tuesday sided with a drug-sniffing German shepherd named Aldo, above, in ruling that police do not have to extensively document a dog’s expertise to justify relying on the animal to search someone’s vehicle. (Nicolas Tucat/AFP)

The Supreme Court on Tuesday sided with a drug-sniffing German shepherd named Aldo in ruling that police do not have to extensively document a dog’s expertise to justify relying on the animal to search someone’s vehicle.

The unanimous court overturned a decision by the Florida Supreme Court. That court had thrown out a 2006 search of a man’s truck after Aldo “alerted” to the smell of drugs, saying police must compile detailed evidence of the dog’s reliability before probable cause to search the vehicle is established.

Justice Elena Kagan said the Florida court had gone too far, and suggested that proper training and certification of the dog — rather than how it has performed in the field — might be enough for law enforcement’s purposes.

“The question — similar to every inquiry into probable cause — is whether all the facts surrounding a dog’s alert, viewed through the lens of common sense, would make a reasonably prudent person think that a search would reveal contraband or evidence of a crime,” Kagan wrote.

“A sniff is up to snuff when it meets that test. . . . Aldo’s did.”

The case was one of two the court accepted regarding drug-sniffing dogs from Florida. It has not decided the other, which concerns whether police may bring a dog to someone’s home and then use the dog’s “alert” to the presence of drugs as probable cause for getting a search warrant.

At oral arguments, that case — involving a chocolate Lab named Franky — caused considerably more debate among the justices.

Aldo’s case came from the Florida Panhandle, where Officer William Wheetley stopped Clayton Harris because of an expired license plate. Wheetley found Harris nervous and shaking, and the man refused Wheetley’s request to search his truck. Wheetley brought out Aldo, and the dog alerted to the smell of something on the driver’s side door handle.

Wheetley used the alert as probable cause to search the vehicle and found the ingredients for making methamphetamine. Wheetley was convicted, but the Florida Supreme Court reversed the conviction.

The Florida high court, citing a growing body of evidence that dogs often make mistakes or are influenced by their handlers, said judges had to consider a long list of specific findings, including how the dogs perform in the field.

Kagan said that went too far, and was at odds with previous U.S. Supreme Court decisions that prescribed “a more flexible, ­all-things-considered” approach. She noted that defense lawyers who had specific concerns about a dog’s qualification could still make such a case to a judge.

The case is Florida v. Harris.

The court also was unanimous in ruling that an American soldier could still pursue custody of his daughter in U.S. courts even though a lower court had allowed the mother to take the child to her native Scotland.

An appeals court said that the move had rendered Sgt. 1st Class Jeffrey Lee Chafin’s lawsuit moot, because international child custody suits must be conducted in the child’s “country of habitual residence.”

But Chief Justice John G. Roberts Jr. said the U.S. Court of Appeals for the 11th Circuit was wrong to rule that Chafin’s only remedy was in Scottish courts.

“Such return does not render this case moot; there is a live dispute between the parties over where their child will be raised, and there is a possibility of effectual relief for the prevailing parent,” Roberts wrote.

Chafin and Scottish-born Lynne Chafin were married in her country in 2006, and their daughter was born the next year. They lived together in Germany until he was deployed to Afghanistan, and mother and daughter moved to Scotland.

Chafin was transferred to Alabama in 2009 and, even though the marriage was in trouble, the family reunited there. The couple agreed to divorce in 2010. Lynne Chafin was deported after her visa expired, and she filed her petition to have Eris join her in Scotland.

A federal judge in Alabama agreed with Lynne Chafin and declined to grant a stay of the order. Mother and child departed that day. When Jeffrey Chafin appealed, the 11th Circuit dismissed his petition. It said that under the Hague Convention on the Civil Aspects of International Child Abduction, there was nothing left for U.S. courts to decide.

Roberts said Jeffrey Chafin may not prevail in U.S. courts, but the uncertainty did not render the case moot.

The case is Chafin v. Chafin.