CLAY COUNTY, Fla. -

The U.S. Supreme Court may not be a dog's best friend.

Justices are considering curbing the use of drug-sniffing dogs because of two Florida cases that test the constitutionality of their searches and argue there isn't enough proof that the dogs are reliable.

Clay County Sgt. Mike Seymour says if the Supreme Court were to limit or remove the department's K9 units, they'd be taking an important tool out of their box.

His dog, Santo, trains every week, and Seymour has few doubts about his reliability.

"He's my partner, he's my friend," Seymour said. "I look after him, he looks after me."

For Seymour, Santo is an invaluable member of the Clay County Sheriff's Office. But the Supreme Court is now questioning whether drug-sniffing dogs across the nation pass the smell test.

"Ninety-five percent that I have been able to find the reason for the alert," Seymour said of Santo. "There were seeds found, there were wrappers found, rolling papers found."

At issue is whether a sniff or "alert" outside a home violates a person's Fourth Amendment rights to search and seizure, and if the dog's training and skills make that "alert" reliable.

"What' the best way to say, 'Yes, he is reliable'?" Seymour said. "Is it in his training records, his street utilization records, or is it a combination of both?"

If the justices rule to limit the dogs' use or find them unconstitutional, the implications could be sweeping. K9 units like Santo not only help find drugs but also locate missing children, detect bombs, protect federal officials, and are routinely used by airport security and in search and rescue operations.

For Seymour, removing Santo or any of the department's seven K9 officers would undermine law enforcement efforts.

"If you have a robbery suspect who crashes a car and flees in the woods, do you really want to send officers out there in the middle of the night to try to find him because he has every advantage, or would you rather that dog go out there and find him? Because he would ultimately give his life for us," Seymour said.

While Seymour admits there is always room for improvement, he hopes the justices see just how important a tool dogs like Santo are and gain a greater understanding of what a dog's nose knows.

Arguments will continue to be heard by the High Court through the end of the year. However, a decision isn't expected until June.