NEW YORK (CBSNewYork/AP) — A New York City judge has heard arguments over the rights of two chimpanzees that advocates hope to free from Stony Brook University, where they’re kept.

Manhattan Supreme Court Judge Barbara Jaffe didn’t make a ruling Wednesday on the fate of Leo and Hercules. But she did entertain nearly two hours of exchanges between a lawyer for the Nonhuman Rights Project and an assistant state attorney general.

NYC Judge Hears Arguments On The Rights Of 2 Chimpanzees

The 8-year-old chimps, who did not attend the hearing, are used for locomotion studies at Stony Brook.

“They’re essentially in solitary confinement,” Steven Wise, president of the Nonhuman Rights Project, told the judge before a crowd of about 100 people packed into the Manhattan courthouse’s ceremonial courtroom. “This is what we do to the worst human criminal.”

Much of the hearing centered on the interpretation of centuries-old legal principles.

The chimps’ advocates say they should be granted a writ of habeas corpus and moved from Stony Brook to a sanctuary in Florida, WCBS 880’s Irene Cornell reported. Wise repeatedly cited legal decisions that granted the writ of habeas corpus to groups historically denied it — including to Native Americans and blacks during the 1800s.

“Chimpanzees are extraordinarily complicated beings,” said Wise. “They’re autonomous and self-determining beings, that it’s a violation of fundamental principles of liberty and equality for us to treat them as things, to treat them as slaves.”

A government lawyer said the case should be dismissed because, among other arguments, the venue isn’t proper. The assistant state attorney general also made the slippery-slope argument, asking, “If chimps are autonomous beings, what about our household pets?”

Christopher Coulston, an assistant state attorney general representing the university, said that it was improper for a court to decide whether the animals are entitled to a writ of habeas corpus and that doing so would be unprecedented, telling Jaffe it is up to the legislature to define personhood in this case.

“The reality is these are fundamentally different species,” he said. “There’s simply no precedent anywhere of an animal getting the same rights as a human.”

He also argued that removing the chimps from Stony Brook and sending them to an island sanctuary is essentially trading one type of confinement for another, further complicating the law.

“They have no ability to partake in human society, the society that has developed these rights,” he said.