Delivering the oath of office in a voice hoarse from cancer treatments, a frail-looking Chief Justice William H. Rehnquist symbolized yesterday what could become the biggest battle in President Bush's second term - the looming possibility of a partisan fight over vacancies on the Supreme Court.
The president's inauguration marked Rehnquist's first public appearance since October, when he began treatments for thyroid cancer. Rehnquist, 80, leaned heavily on a cane, and the tube from his tracheotomy surgery was visible at the loose collar of his signature judicial robe, its distinctive four gold stripes on each sleeve.
Rehnquist was the last dignitary to join the inaugural ceremony, arriving after Bush was seated. He was on the platform only about 15 minutes, turning slowly to leave after he had delivered the 35-word oath of office and then added firmly, "Congratulations."
His presence at the most public of ceremonies put to rest speculation that Rehnquist might be too ill to swear in the president, an act that just eight times in the nation's history has not been carried out by the chief justice. But his weakened state added to speculation that Rehnquist will retire in June, at the end of the court's term, if not sooner.
"That's the big unspoken event of the next term, and it's not something that Bush can address in the inaugural speech," said Larry J. Sabato, a political science professor at the University of Virginia, who said it was unprecedented for the chief justice to arrive after the president and leave before his inaugural address. "It's like the elephant in the room."
For three months, Rehnquist's future has been the subject of much discussion even as he dropped from sight. He has been absent from the bench for arguments since mid-October, though he has indicated that he is participating in cases and working part time in recent weeks from his chambers.
"He actually doesn't look as bad as I feared he might - he's a man of great resiliency, obviously, and a great sense of duty," said Arthur D. Hellman, a University of Pittsburgh law professor who closely follows the court. "It's obviously wonderful that he could make this public appearance, but the work of a Supreme Court justice, and the chief justice, is a day-in, day-out obligation that requires a great deal of time and concentration."
"He looks good, he looks animated," said David N. Atkinson, a law and political science professor at the University of Missouri, Kansas City, who has written about Supreme Court departures.
But "I don't know how one can be chief justice in absentia," Atkinson said. "There are so many duties. ... You can't just run the chief justiceship from your home."
There has not been a vacancy on the Supreme Court in a decade, and a Rehnquist retirement would enable Bush to appoint his first justice. Already, Democrats have vowed to contest any replacement who might shift the court's balance on such high-profile issues as abortion, affirmative action and states' rights.
That fight could just be the warm-up. Some observers say Bush could have the chance to appoint up to four new justices to the aging and increasingly frail court.
Justice Clarence Thomas, 56, is the only member under the age of 65. Rehnquist is the fourth member of the current court to face cancer. Justice Sandra Day O'Connor, 74, had breast cancer, and Justice Ruth Bader Ginsburg, 71, was treated for colon cancer. Justice John Paul Stevens, the court's eldest member at 84, has undergone surgery for prostate cancer.
Rehnquist has released little information about his illness, but specialists have said the combined treatment of radiation and chemotherapy, with the earlier tracheotomy, indicate that he has anaplastic thyroid cancer, which is fatal in nearly every case.
Dr. Rodney Taylor, a head and neck surgeon at the University of Maryland Medical Center, said the fact that the tracheotomy tube was visible at the chief justice's throat was consistent with a diagnosis of incurable cancer. But Taylor said he was impressed with Rehnquist's inaugural performance.
"I thought he looked a little bit peaked and a little bit frail," Taylor said. "But for an 80-year-old who's been through chemotherapy and radiation treatments, I thought the chief justice showed the vigor that he's known for."
Rehnquist's eight court colleagues looked on as he slowly descended the stairs to administer the oath of office. To loud applause, Rehnquist was introduced by Republican Sen. Trent Lott of Mississippi, who called him the "Chief Justice of the Supreme Court of the United States."
The correct title is Chief Justice of the United States, legal observers noted.
"That's something that Rehnquist is actually a stickler for," Hellman said. "It must have pained him to hear it. You'd think at a ceremony this important, they could have gotten that right."