On January 19, 1999, President Clinton gave his penultimate State of the Union address. During that time, the Senate impeachment trial was ongoing. Indeed, earlier that day, his lawyers had wrapped up their first day of arguments. Later that evening, Chief Justice Rehnquist, as well as Justices Stevens and Scalia were absent from the address. Todd Peppers and Micheal Giles speculated that the "Chief Justice effectively 'recused' himself from attending the 1999 State of the Union Address, since he was currently presiding over the impeachment trial in the United States Senate."

One year later, President Clinton gave his final state of the union address on January 27, 2000. All nine Justices stayed home from the address. The Court sent a two-sentence message to the Sergeant at Arms:

"Justices of the court had planned to attend the State of the Union address, but travel changes and minor illnesses have intervened. No justices will be in attendance, but they do thank you for the invitation to be present for the address."

The Times observed that several of the Justices seemed to have legitimate reasons to skip it:

The two Clinton appointees to the court, Justices Stephen G. Breyer and Ruth Bader Ginsburg, cited health reasons for skipping the speech. Justice Ginsburg has been undergoing radiation treatment after colon cancer surgery. Justice Breyer sent Mr. Clinton a note saying he wanted to attend, but he was homebound with the flu. Justice John Paul Stevens is taking care of his wife, who recently had hip replacement surgery. Justice Clarence Thomas is in New Orleans, where his brother died on Sunday. Justice Anthony M. Kennedy has to be in New York to deliver a speech on Friday. There was no explanation from the court for the absences of Chief Justice William H. Rehnquist or Justices Antonin Scalia, Sandra Day O'Connor or David H. Souter. Last year, when Chief Justice Rehnquist was absent, he stayed away because he was presiding over the president's impeachment trial.

Ted Olson offered some speculation:

The White House had no comment on the court's truancy, but others did. ''I'm just astonished,'' said Theodore B. Olson, a Washington lawyer and former Justice Department official in the Reagan administration. ''On the other hand, these things have become so ritualistic and boring that it would be easy to find more entertaining alternatives.'' ''Maybe,'' Mr. Olson added, ''enough of them saw what the chief justice went through during the impeachment trial that they decided they didn't want to go near the place.''

Will any of the Justices skip the 2020 address? If Roberts follows Rehnquist's practice, he may skip the address. We know that Justices Alito and Thomas do not attend the addresses as a matter of principle. And Justice Ginsburg has never attended a State of the Union address with a Republic president. (Yes, her attendance pattern is that obvious.). If Roberts is absent, Breyer will be the most senior-associate Justice present. He will be flanked by Justices Sotomayor, Kagan, Gorsuch, and Kavanaugh.