McDougall sued Charlot Lamm, the other dog's owner, for compensatory damages and the emotional distress she said she suffered from seeing her pet, Angel, violently killed. The other dog has since been euthanized.
The provision she sought to use came from a 1980 ruling that found that seeing the death of a close family member causes emotional distress. Since then, state courts have slightly broadened the group from relatives. A woman whose fiance was killed was allowed to make the claim, as was a man whose 5-year-old neighbor died despite the man's attempt to rescue him.
In court filings, McDougall said the dog was a constant companion, particularly after she and her husband separated and their three children grew up and moved out.
A lower court ruled that the compensation for the dog's loss should be $5,000 - nearly four times the $1,300 cost of a puppy of the same kind. But it dismissed the emotional distress claim.
In a unanimous decision, the Supreme Court agreed with that ruling.
"Although we recognize that many people form close bonds with their pets, we conclude that those bonds do not rise to the level of a close familial relationship or intimate, marital-like bond," Justice Helen Hoens wrote in her opinion.
Lamm's lawyer, Brian O'Toole, said that as a dog lover, he found the case to be painful and poignant. But he said the court got it right. If a person could be compensated for the loss of a pet, which is considered property, it could open the door to emotional damages for destroyed family heirlooms, he said.
"Where does it end?" he asked.
McDougall's lawyer, Lewis Stein, said he could not overcome the Supreme Court's fears that the judicial system would be overwhelmed with claims and that juries would have a tricky job separating real from imagined emotional distress if McDougall's claim had been allowed to stand.