US Attorney Steven Wise believes that chimpanzees are people too.
For that matter, so are dolphins, elephants, gorillas and orcas.
He is on a crusade to prove that, as a matter of law, chimps are people too.
He made his argument at the TED Conference that wrapped up in Vancouver, Canada on Friday.
"I had to invent the field of animal jurisprudence," Wise told AFP at TED. He added, "Coming here is implicit affirmation that people are interested in what we have to say."
Wise argued that apes, chimps, elephants and orcas are as entitled to the rights of "persons" under law as are people or corporations.
Legal systems around the world have granted rights of personhood to holy scripts, mosques, companies, and even a river.
"Personhood is not a biological concept, it is a public policy concept," Wise said.
"The legal system decides it; human being is not synonymous with person."
Wise has devoted decades to the cause, which is now making its way through courts in the US state of New York.
Wise, president of the Nonhuman Rights Project, is hoping a legal tactic, successful in getting a slave legally transformed from property to person in a historic case in Britain, will do the same for chimpanzees and other animals.
He will use the writ of habeas corpus, in which judges order prisoners or detainees brought before the court. Such writs, by definition, assign rights of personhood to those targeted.
Members of the project found chimpanzees in abysmal conditions in several parts of the state of New York, then filed for writs of habeas corpus in respective courts to get the animals moved to a refuge.
Victory would come in the form of a non-human animal being legally recognized as a person for some purpose, no matter how limited.
Wise is working with lawyers in Europe, Argentina and other parts of the world.
The Nonhuman Rights Project is looking to hit US courts with its next case, on behalf of circus elephants, late this year.