For the first time in US history, a judge has decreed that a pair of chimpanzees held at a university research facility are covered by the same laws that govern the detention of humans, effectively rendering the animals as legal "people" in the eyes of the law. New York Supreme Court Justice Barbara Jaffe said that the apes, held at Stony Brook University for research purposes, are covered by a writ of habeas corpus — a basic legal principle that lets people challenge the validity of their detention.

However, hours later, Jaffe amended her court order to remove the habeas corpus language, essentially reversing the earlier decision.

The non-decision comes two years after the Nonhuman Rights Project, an animal rights group, brought legal cases in a bid to free four chimpanzees. The group said the animals — Hercules and Leo at Stony Brook university, and two others on private property — were being unlawfully imprisoned, and should be relocated to a sanctuary. Three lower court judges dismissed the cases as they were raised in 2013, but the Nonhuman Rights Project appealed, eventually convincing Jaffe that the animals were sufficiently intelligent to grant them what amounts to basic human rights — but only temporarily.

The animal rights group wants the apes moved to a sanctuary

Jaffe has ordered a Stony Brook representative to appear in court on May 6th to reply to the Nonhuman Rights Project's petition that the animals are being held unlawfully. It could be that the judge organized the hearing to listen to both sides of the case before making a decision, and will ultimately decide that Stony Brook can keep the apes — Richard Cupp, a law professor at California's Pepperdine University told Science it would be "quite surprising" if the judge made "a momentous substantive finding" that chimps were legally people without both parties being able to have their say.

But Natalie Prosin, the Nonhuman Rights Project's executive director, said after the original decision that regardless of whether Hercules and Leo are afforded legal personhood after the hearing, the group intends to use the judge's ruling in future cases. "We have scientific evidence to prove in a court of law that elephants, great apes, and whales and dolphins are autonomous beings and deserve the right to bodily liberty," she said. "[This ruling] strengthens our argument that these nonhuman animals are not property."

Update, 4/21/15, 7:15PM ET: According to Science, the judge who said that a pair of chimpanzees were covered by a writ of habeas corpus has amended her court order to remove that wording. The May 6th hearing to determine whether the chimpanzees are being held unlawfully appears to still be on schedule. This story has been updated to reflect these changes.