WAREHAM — The owners of a dog ordered euthanized by the Marion Select Board appealed the decision in a hearing Tuesday, July 19 at Wareham District Court.

Much of their argument centered around the specifics of a previous decision by the select board to deem Stella a “dangerous dog” and the geographical limitations of that order.

The select board unanimously voted on June 9 to have Stella, a 130-pound mastiff owned by David and Jennifer MacDonald of Marion, humanely euthanized after Stella attacked and seriously injured a dog while unmuzzled.

That incident happened May 17 in Watertown, Conn. when Stella was accompanying Jennifer MacDonald to a visit to The Taft School, a private institution where her son was attending an event.

Stella had been deemed a “dangerous dog” by a previous select board after she killed a dog on the playground at Sippican School in Marion in 2018.

As part of that determination, the dog was ordered to be muzzled when off the MacDonald’s property.

During the hearing Tuesday, David MacDonald, serving as attorney for his wife, argued that the conditions only applied in Massachusetts and did not extend to Connecticut, where the incident happened that prompted the euthanization order.

Gregg Corbo of KP Law, representing the Town of Marion, disputed this. The statute that the dangerous dog determination falls under “doesn’t say that it is not effective outside’’ Massachusetts and there is “no reason why this order would not have applied to the state of Connecticut.”

In recounting the events of that day, Jennifer MacDonald said that she and the dog were sitting alone in a grassy section of a parking area at the school.

Stella was on a leash but not muzzled, she said. Jennifer MacDonald had the muzzle in the car, she said, because she “didn’t see any need for a muzzle because we were in Connecticut and understood the order [applied only] within the state” of Massachusetts.

MacDonald said there was “no one around’’ when Stella “leaped up as if she was surprised.”

MacDonald was “pulling on her leash when she lunged.”

Stella then attacked Milo, a 20-pound Cockapoo that was on a walk with her owner, Maria Quatrano, who said via a Zoom appearance that she lives nearby and often walks her dog in the area.

Milo suffered extensive injuries, according to Quatrano, including a torn ear, 13 puncture wounds in his neck and a torn trachea, which affected the dog’s breathing. Milo was kept in an oxygen chamber to assist with his breathing issues, Quatrano said.

The dog will likely need further treatment, she said, including possible pain management and antidepressant medication. He no longer wants to take walks, which she said had been a regular part of their routine. “He’d rather be quiet and in his bed,” she said.

Jennifer MacDonald said that she immediately put Stella in the car and drove to the local police to report the incident. “I was trying to be responsible,’’ she said. “That felt like the right thing to do.” She also offered to pay for a portion of the veterinary bill.

“We’re dog people,” David MacDonald said, and Jennifer MacDonald agreed that she feels “awful” about what happened. But she said she also feels badly for her dog, who had an “awful life” prior to her being adopted by the MacDonalds.

David MacDonald also argued in his official written appeal that the town violated open meeting law. He stated there had been discussions indicating that a decision had been made prior to the June 9 hearing to take the dog from the MacDonalds and place her in a shelter.

In his closing statement, David MacDonald noted that Stella is “docile” with people and his other family pets and can be restrained to their property or moved out of state with relatives or friends willing to take her.

“She’s loved and she’s special,’’ he said.

Corbo countered that Jennifer MacDonald showed “blatant disregard” to the previous conditions, which she “knowingly violated” by having the dog unmuzzled.

Stella attacked without provocation, Corbo said, and three or four people were needed to get the dog to release its grip.

The dog is “clearly a dangerous dog,” he said.

A decision was not immediately made by Manchester.