BACK FROM its Easter break, the Senate confirmed its first judicial nomination of the year on Tuesday, and it did so unanimously. That’s the sort of action we expected when Senate Majority Leader Mitch McConnell (R-Ky.) promised a return to regular order after November’s election.

But that small glimmer of responsibility is overshadowed by the unconscionably shabby treatment the Senate has shown to Loretta Lynch, President Obama’s well-qualified nominee for attorney general. The sitting U.S. attorney in Brooklyn, Ms. Lynch was an outstanding choice who should not have had any trouble getting confirmed — five months ago. Instead, lawmakers have used the opportunity of her nomination to exert legislative leverage and score political points.