Last week, the Senate confirmed Judge Ketanji Brown Jackson to a seat on the U.S. Supreme Court. This raised the question of whether the President could go ahead and appoint Jackson to the High Court, even though the seat for which she was nominated is still occupied by Justice Stephen Breyer. A newly released memo from the Office of Legal Counsel in the Department of Justice addresses this question. The memo, "Authority of the President to Prospectively Appoint a Supreme Court Justice," is dated April 6, was signed by Assistant Attorney General Christopher Schroeder, and suggests presidents may appoint confirmed...