“Once a court recognizes that a nonhuman animal has the capacity to possess a legal right,” Wise says, “its determination of whether she actually has the rights she claims will appropriately shift from the current irrational, biased, hyperformalistic and overly simplistic question ‘What species is the plaintiff?’ to the rational, nuanced, value-laden principles- and policy-laden question: ‘What qualities does the plaintiff possess that are relevant to the legal right she claims?’ ”

In an address delivered in April 2012, at Pace University law school, Wise likened animals today to human slaves in 18th century England — invisible to the legal system, beings without rights. He cited the ruling of the British judge, Lord Mansfield, in the 1772 Somerset case that opened the door for the abolition of human slavery in England.

Now Wise says he is looking for a modern-day Mansfield, a “substantive common-law judge” who might rule — under the general rubric of “dignity” — in favor of an animal’s right to bodily liberty and bodily integrity. He feels that the breakthrough will come if one state high court declares that a nonhuman is a legal person — in the eyes of the law.