On the first day of its new term, the U.S. Supreme Court began delving into a case centering on the scope of the Endangered Species Act. Based on the Oct. 1 oral arguments in the case, Weyerhaeuser Co. v. U.S. Fish and Wildlife Service, the court seemed divided. With one vacancy on the court, eight justices took part in the hearing, raising the possibility of a 4-4 ruling later this term.

Liberals on the court quizzed attorney Timothy Bishop, representing the landowners who brought the case, about their positions. Conservative justices focused their questions on Deputy Solicitor General Edwin Kneedler, representing Fish and Wildlife, asking, for example, about the costs of habitat designation.

The case deals with the dusky gopher frog, listed as endangered in 2001, and whether the agency went too far in declaring a 1,544-acre tract in Louisiana “critical habitat” for the frog, even though it does not now live on the site. Fish and Wildlife determined the land has attributes of a place for the animal to live and should be categorized as critical habitat.

The landowners, which include Weyerhaeuser, challenged the agency’s decision. They planned commercial and residential development and timbering on the land.

A federal district court ruled in favor of Fish and Wildlife. In 2016, an appeals court upheld the lower court’s decision, prompting the landowners’ appeal to the Supreme Court.

At oral arguments, Justice Elena Kagan asked Bishop whether a modest change to another tract to make it suitable habitat for the frog would be acceptable. If requiring only minimal changes, Bishop said he wouldn’t rule it out. But he said, “That isn’t this case.” Kagan said the Endangered Species Act states “that habitat isn’t just sort of there and perfect always, that habitat requires things to be done to it” to protect wildlife.

Chief Justice John Roberts asked Kneedler whether there are any limits on the amount of required habitat restoration. Kneedler replied that “it has to be, according to [Fish and Wildlife], reasonable efforts.” Justice Samuel Alito asked, “Well, what’s the definition of reasonable?”