The horse had been left outside and underfed by his previous owner, who last summer pleaded guilty to criminal neglect. And now Justice, who today resides with other rescued equines on a quiet wooded farm within view of Oregon’s Cascade mountains, is suing his former owner for negligence. In a lawsuit filed in his new name in a county court, the horse seeks at least $100,000 for veterinary care, as well as damages “for pain and suffering,” to fund a trust that would stay with him no matter who is his caretaker.

The complaint is the latest bid in a quixotic quest to get courts to recognize animals as plaintiffs, something supporters and critics alike say would be revolutionary. The few previous attempts – including a recent high-profile case over whether a monkey can own a copyright – have failed, with judges ruling in various ways that the nonhumans lacked legal standing to sue. But Justice’s case, the animal rights lawyers behind it contend, is built on court decisions and statutes that give it a stronger chance, particularly in a state with some of the nation’s most progressive animal protection laws.