A shifting Court

This is a smarter-than-usual analysis of what happens when the membership of the Supreme Court changes:
I used to think the impact of a seat change is best measured by comparing the new justice to the old one, but that’s wrong. What we really want to know is what happens to the median (or swing) justice. The median justice provides the crucial fifth vote on cases that divide along ideological lines. So when Alito replaced O’Connor in 2005, the Court’s median justice switched from O’Connor to Kennedy. That was a slight rightward shift for the Court as a whole — but a smaller one than might be expected given Alito’s much more conservative record than O’Connor’s.
With Kavanaugh seated, the consensus is that Roberts will become the new median justice. This is a substantial movement to the right for the Court, especially on social issues where Kennedy typically voted with the liberals. Interestingly, in the short run it doesn’t matter where Kavanaugh fits in among the Court’s conservatives. Right now, Roberts is the least conservative, Thomas is the most, and Alito and Gorsuch fall in between. But whether Kavanaugh is closer to Roberts or to Thomas should have little effect on the Court’s rulings, since Roberts as the median justice will control the outcomes.
Where Kavanaugh’s ideology becomes important, however, is in determining the effect of replacing Ginsburg. If Kavanaugh turns out to be an Alito/Gorsuch–type justice, and so does Ginsburg’s replacement — let’s label that mystery person Amy B. — the median justice would be someone from the Alito-Gorsuch-Kavanaugh-Amy B. bloc. If you’re a conservative, shifting the median that far to the right would be a dream come true. It may cause a sea change in constitutional law.
But what if Kavanaugh turns out to be an ideological clone of Roberts? Then replacing Ginsburg with Amy B. would, in theory, have no effect on subsequent cases. The median justice would still have a Roberts-type ideology, and the Court’s decisions would continue to reflect his rightward but incrementalist approach.


Grim said...

There's an additional consideration which is important: the effect the justices have on each other. A new justice who is further right can move the court's personal Overton window, especially if he or she is also a persuasive and personally-well-liked figure.

E Hines said...

An additional interpersonal impact consideration is whether the new Justice is a reasoned, logic-oriented jurist rather than an ideological firebrand in the Thurgood Marshall mold.

Eric Hines

Assistant Village Idiot said...

Good points all. The Supreme Court, like any group, is dynamic and not as predictable as people generally think.

douglas said...

There's also one other possible scenario (thoughI'll admit seems a longer shot now)- what if Kavanaugh is closer to Kennedy than Roberts? That would be disappointing. Still, every appointment is important, and the flaw in this thinking is that any justice can retire or have tragedy befall them at any time, so we don't know who is next to be replaced.