What can John Roberts do about Clarence Thomas?

The Supreme Court's reputation has taken a hit in recent days with the revelation that Justice Clarence Thomas ruled on a case that concerned his wife's efforts to overturn Donald Trump's election loss, but there's not much Chief Justice John Roberts can do about it.

Thomas did not recuse himself from cases involving the 2020 election or the Jan. 6 insurrection, although his wife Ginni Thomas was communicating with former White House chief of staff Mark Meadows about ways to keep Trump in power, but CNN legal analyst Joan Biskupic said the chief justice don't have enough power to take action.

"Despite his elevated title, Roberts has little real authority with his colleagues," wrote Biskupic, a Supreme Court biographer. "He controls the assignment power of cases when he is in the majority and oversees the running of the building. But each justice is appointed for life and can be removed only through impeachment."

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Congressional Democrats have asked Thomas to recuse himself from future Jan. 6 cases and provide a written explanation for his previous failure to do so, and they called on Roberts to commit to establishing a binding code of conduct for the court.

"Justice Elena Kagan told a House committee in March 2019 that Roberts was considering such action," Biskupic wrote. "But the matter faded after that. The chief justice has said they generally abide by the ethics code that covers lower court judges. Separately, the justices are bound by a federal law that says they should disqualify themselves from cases if their 'impartiality might reasonably be questioned.' Whether that law could ever be enforced against the justices has never been tested."