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And Now Over to You, John Roberts

The chief justice has as his task to preside over the senate trial ahead. But his role is a limited one, and he should be able to manage it easily without putting his or the Court’s legitimacy at risk.

Now that President Donald Trump has been impeached, the nation’s attention will soon turn to Chief Justice John Roberts, who is constitutionally obliged to preside over the forthcoming Senate trial. This may seem like an impossibly difficult task: How will he respond to potential Republican efforts to truncate the proceedings with a premature vote? And more challenging still, at a time when the Supreme Court stands accused of politicization and ideological polarization, how will he resolve contentious disputes without putting his own neutrality, and that of the judiciary, in question?

For answers, the country doesn’t have to look further than the hands-off approach perfected by Roberts’s predecessor, Chief Justice William Rehnquist, who rightly recognized that the Senate—not the chief justice—commands the proceedings. The senators themselves will determine just how hard or easy Roberts’s job will be, but as Rehnquist demonstrated, the Senate’s rules and historically heavy reliance on its own past practices prevent it from forcing a skillful presider into an uncomfortable corner.

To be sure, Rehnquist was uniquely suited to preside over President Bill Clinton’s impeachment trial. The respect he commanded from the Senate flowed in part from the fact that he happened to be an impeachment expert: Years before Clinton’s impeachment trial, Rehnquist, an amateur historian, published a well-received book detailing the impeachments and acquittals of Supreme Court Justice Samuel Chase and President Andrew Johnson. The Senate was aware of Rehnquist’s authority on the process—its solemn objectives and potential pitfalls—as well as his views on the importance of those acquittals. In Rehnquist’s assessment, the conviction of Chase or Johnson would have upset the checks and balances established by the Constitution, undermining judicial review (in the case of Chase) and executive authority (in the case of Johnson) and moving the nation closer to a regime of congressional supremacy.

Roberts does not have similarly articulated views on the subject. But the suggestion that he will do anything to inject himself into the political fray or serve as the ultimate decider on key issues not clearly addressed by the Senate rules or precedents requires ignoring his well-established commitment to judicial nonpartisanship and sensitivity to respecting the powers and competencies of the various branches. The suggestion also reflects, at best, confusion over his duties as the official presider.

One popular analogy for understanding the Senate phase of the proceedings is a standard civil or criminal trial, in which the chief justice plays the role of judge while the senators act as the jury. It’s an appealing analogy, but also a very bad one. Judges decide law, and juries assess facts. In an impeachment trial, by contrast, the senators will make virtually all the important legal determinations as well as the factual ones. The Senate’s function in deciding the legal issues is no small point, given that facts have not been the primary point of disagreement in any past presidential impeachments. The disagreements have been largely over the legal significance of those facts.