NEW YORK – They may not know it, and they most certainly will not be in attendance, but Hercules and Leo will have their day in court.

A judge in Manhattan has ordered a hearing that will touch upon the continuing debate over whether caged chimpanzees can be considered “legal persons,” in the eyes of the law, and thus sue, with human help of course, for their freedom.

At issue in this case – one of several percolating though the courts in New York and elsewhere – is the fate of Hercules and Leo, a pair of chimpanzees that their legal representatives say are “unlawfully detained” at a university on Long Island.

The order, by Justice Barbara Jaffe of New York state Supreme Court, directed officials at Stony Brook University to show cause for holding the two chimps, at a May 6 hearing.

Whether it is a great day for apes, however, remains to be seen. Jaffe’s decision, issued on Monday, was largely administrative and gave little if any indication of her feelings on the merits of the case. Animal rights supporters initially hailed it as a major breakthrough, citing the fact that Jaffe’s order had included the words “writ of habeas corpus,” a legal means to address the unlawful detention of prisoners.

But as news of the order spread, Jaffe amended it on Tuesday, striking the language about a writ and emphasizing that it was simply a formal way of directing the university to her courtroom to present its case.

“All this does is allow the parties to argue their case in court,” said David Bookstaver, a spokesman for the New York state court system.

Still, supporters seemed emboldened by the judge’s decision to sign off on the order, which was drafted by the Nonhuman Rights Project, a group that has been active in promoting a legal theory that some animals, such as chimps, are “legal persons” with the right to “bodily liberty.”

Natalie K. Prosin, the executive director of the group, said that she was pleased that Jaffe had asked the university to show cause for the chimps’ captivity. Prosin said she was “grateful for an opportunity to litigate the issue.”

Recent legal efforts have not been successful in New York; in December, a five-member state judicial panel in Albany unanimously ruled against Prosin’s group in its attempt to have an older chimp named Tommy released from captivity.

Still, in her three-page order, Jaffe did set the hearing on Hercules and Leo, asking the university to show cause as to why the animals should not be released to an animal sanctuary in Florida, as the Nonhuman Rights Project is seeking.

Eric T. Schneiderman, the state attorney general, who is charged with defending state agencies, including universities, in lawsuits, had no comment on the chimps. Lauren Sheprow, a spokeswoman for Stony Brook, part of the State University of New York system, would say only that it “awaits the court’s full consideration on this matter.”

Critics of the animal rights argument expressed dismay that Jaffe had granted the hearing.

“Nonhuman animals do not have legal rights any more than they have legal responsibilities,” said Bob Kohn, a technology lawyer in Manhattan who has filed briefs opposing efforts to secure human rights for chimps and other animals. “For a court to hold otherwise would have tremendous adverse legal and moral implications for mankind.”

Some legal experts, however, seemed to offer support for the idea that animals could file suit for their freedom. Laurence H. Tribe, the Harvard Law School scholar, said in an email that he believed that habeas corpus should be extended to “other beings whose capacities are limited but who are potentially capable of bearing rights,” a category he contended would eventually include chimps like Hercules and Leo.

Tribe added that Jaffe’s decision was “a legally sound and suitably cautious step forward in the struggle to extend legal protections,” regardless of “whether or not we are yet ready to crown those others with the title of ’human person.’”

Prosin said her group was saying not that animals were people but that they were “autonomous beings, who are self-aware and self-directed.”

Prosin said she had never met Hercules or Leo, who are believed to be young chimpanzees about 7 or 8 years old and who, like all apes, have much of the same DNA as humans. That aside, she added that her group was not asking for broad human rights, like voting or legal responsibilities, for Hercules or Leo, but was merely seeking their freedom.

“We’re only asking for one specific right,” she said. “And that’s one fundamental right.”