COLUMBUS — A dog must not have been previously designated as dangerous under Ohio law for an owner to be prosecuted when the pet attacks someone, the Ohio Supreme Court held Tuesday.

But the court went on to say in a Hamilton County case that the dog owner’s conviction for failing to confine the animal should be reversed because the prosecution failed to meet its burden of proof.

The decision as to whether a prior dangerous-dog designation is required in such a case resolves a dispute raised by two separate appellate court rulings that reached different conclusions.

The decision stems from a 2016 incident for which Joseph Jones, of Cincinnati, was prosecuted for letting his American pit bull terrier off its leash. He said he removed the leash so his dog could protect him from an approaching stray. The two dogs interacted well together, but the stray then attacked a small Chinese Crested Hairless dog being walked by Alyssa Rushing, who had just exited the same apartment building.

She maintained that Jones’ dog bit her wrist and hand and pulled her to the ground during the attack.

Jones was convicted under an Ohio law that prohibits an owner from failing to confine a “dangerous” dog while in public. His 30-day jail sentence for the fourth-degree misdemeanor was suspended while he successfully completed a six-month probationary period.

But he appealed his conviction, arguing that he should not have been convicted of failing to leash a dangerous dog if the animal had never been designated as such under Ohio’s dangerous-dog law. The dog must have a prior history of being dangerous, he argued.

The Supreme Court disagreed with Mr. Jones but it went on to say that his conviction for failing to confine the animal should be reversed.

The court agreed with the prosecution that it needed only to prove that the dog’s conduct was enough to satisfy the definition of a dangerous dog under the law. Legislators did not specifically require a prior designation in its dangerous-dog law, the court said.

“Because the dangerous-dog designation turns on the dog’s past behavior, the statute provides fair warning to a dog owner that he or she may be subject to the dangerous-dog provisions (of the law),” wrote Justice Melody Stewart for the majority.

But the court went on to determine that the prosecution failed to prove beyond a reasonable doubt that Jones’ dog, without provocation, had caused a non-serious injury to a person, killed another dog, or was a three-time offender.

While the court was unanimous in the final outcome for Mr. Jones, it split 5-2 on the question of whether a prior dangerous dog designation was necessary.

Justice Sharon Kennedy, in a concurring opinion, wrote that the court must look at the broader law in its entirety—including provisions dealing with dog registration, kennels, and dog wardens—to judge lawmakers’ intent.

She noted that the majority’s determination allows for a dangerous-dog designation to occur simultaneously with a prosecution for failing to to confine a dangerous dog.

“If that is true, then why did the General Assembly provide a civil legal process (in state law) by which a court may ultimately determine whether a dog is dangerous and that also affords the owner of that dog a right of appeal?” she asked.

The decision comes as state lawmakers have before them House Bill 37, which would toughen penalties for owners when their dogs attack. It could allow the owner of an attacking dog to be charged with a fifth-degree felony carrying up to a year in jail–even if the dog had not previously demonstrated threatening behavior.

State law provides for three classifications of problem dogs—nuisance, dangerous, and vicious—based upon the animal’s past behavior. The more severe the classification, the more responsibilities that the owner must meet.

The bill would not restore Ohio’s former law that automatically labeled dogs falling under the broad category of ‘pit bull’ as vicious.