In this image from video, President Pro Tempore of the Senate Sen. Chuck Grassley, R-Iowa., swears in Supreme Court Chief Justice John Roberts as the presiding officer for the impeachment trial of President Donald Trump in the Senate at the U.S. Capitol in Washington, Thursday, Jan. 16, 2020. (Senate Television via AP) No one should be surprised by Chief Justice John Roberts’ decision today to join in the judgment of the Court, but not the opinion of Justice Breyer, invalidating…