A presidential impeachment trial in the Senate is one man's worst nightmare. That man isn't President Donald Trump, however. He'll take it in stride. It's Chief Justice John Roberts, who will have to preside.
Roberts has devoted his whole career to trying to keep the Supreme Court from being seen as a partisan body. That started with the famous baseball analogy he offered at his Senate confirmation, according to which the justices are like umpires who call balls and strikes. The comparison is pretty dubious: balls and strikes aren't infused with controversial moral questions like when life begins and who can marry whom. But Roberts was trying to illustrate his ideal of a justice who stays out of the partisan fray of team spirit.
Since then, Roberts has made a number of important rulings perhaps intended to keep the court from appearing too partisan. For example, he broke with his conservative colleagues to save the individual mandate in the landmark Affordable Care Act case (even though, in the same judgment, he gutted the act's Medicare expansion) and also sided with the liberals in a 5-4 decision that kept a citizenship question off the 2020 census questionnaire.