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Even as the fight over Kavanaugh's nomination to the Supreme Court continues, the court began a new term today. And it did so with only eight justices. Republicans had hoped to seat Judge Kavanaugh in time for the new term. Of course, that did not happen. NPR legal affairs correspondent Nina Totenberg was at the court today and has this report.

NINA TOTENBERG, BYLINE: The day played out like a Hollywood movie, with the action moving back and forth between the three branches of government. At the White House today, the president held a sun-dappled press conference to talk about his new trade deal. But inevitably, he faced Kavanaugh questions - among them, given how partisan Kavanaugh's performance was last week, could the president assure the American people that Kavanaugh would deliver impartial decisions if he's confirmed to the court? The president never really answered the question.

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PRESIDENT DONALD TRUMP: Well, you'll have to ask him that question. But I can tell you he's been treated horribly.

TOTENBERG: Meanwhile, behind the scenes at the Capitol, the Republican leadership was trying to limit the FBI investigation that was forced upon them last week when three key Republicans said they would not support Kavanaugh unless the FBI background investigation was reopened. But what that investigation entails remains an open question, with Republican Senate Majority Leader Mitch McConnell stressing the limited nature of the investigation and President Trump saying he wants a comprehensive but short investigation.

While all these machinations were taking place, the Supreme Court opened a new term and began hearing arguments. Once again, as in 2016, the court has only eight justices. Back then, Senate Republican Leader McConnell blocked any hearing for President Obama's nominee to the court for almost a year. But back then, Justice Anthony Kennedy, a conservative who sometimes sided with the court's liberals, was still on the court. Now he has retired.

So today, for the first time in well over 30 years, there was no justice like Kennedy or Sandra Day O'Connor - both appointed by President Reagan - who sits ideologically at the center of the court. And today, the liberal-conservative split was apparent in the first case to be argued, a challenge to a regulation under the Endangered Species Act. The central player in the case is the dusky gopher frog, which sounds a bit like this.

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TOTENBERG: The species lives in only one place in Mississippi and is in danger of becoming extinct when the ephemeral pond that it lives and breeds in is gone. Ephemeral ponds dry up periodically and have no fish, so the frogs' eggs don't get eaten. At issue in the frogs' case is whether the Fish and Wildlife Service can designate an area in Louisiana where the frogs once lived as a critical habitat so that, at some point in the future, the frogs may be moved back to this area where there are more ephemeral ponds.

Weyerhaeuser, the timber company which leases the land, has challenged the designation as a potential threat to any future development plans. After the argument, on the steps of the court Noah Greenwald, the endangered species director at the Center for Biological Diversity, explained why Congress enacted the Endangered Species Act in the first place.

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NOAH GREENWALD: The web of life that we ourselves depend on is built of species. You know, ecosystems are made of species. We all depend on species for our food, for our medicines, for clean air, for clean water.

TOTENBERG: Weyerhaeuser's lawyer did not come to the microphones. But inside the court, the four liberal justices pointed to language in the Endangered Species Act that allows reasonable actions like this one, and the court's four conservatives complained that the Fish and Wildlife Service doesn't say what reasonable is. A 4-to-4 tie would mean the lower court ruling stays in place, meaning Weyerhaeuser loses. How fast the court gets a ninth justice depends on how quickly the Senate can hop along.

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TOTENBERG: Nina Totenberg, NPR News, Washington.

(SOUNDBITE OF MUSIC) Transcript provided by NPR, Copyright NPR.