So there is this prof, Joel Levine that I like who has some methodology for taking non-numerical data and forcing it to a number line. My personal favorite is putting political groups on a number-line by means of religious affiliation. I think it is a great idea. For what follows, I take for granted that I have a single conservative/liberal number for each SCOTUS justice and candidate. You could ask for more numbers but as they tend to correlate well with conservative/liberal (but not as well as in party politics), I don’t think it is worth overcomplicating our treatment. You could break up principle components or something and deal with multiple axis but that is orthoganal to the point I want to make.
So I put the 9 current justices in and 9 numbers come out. Since the numbers are only meaningful in the relative sense, I can huck two of them: one to define a zero and another to define a scale. If you understand the details of the system, you’d be able point out that there was already a scale to the numbers. In the politics/religion case, the political units were in terms of delta-religion. But in this case, that scale has less meaningful units than, say, (Ginsberg—Scalia)s.
For example, we could say something like,
Kennedy = 1 O’Connor + -.3 (Ginsberg—Scalia)’s.
which we could call simplify to,
Kennedy = -.3,
by making the units implicit.
So people are going to have the opportunity to try to “change the make-up” of the court. There is someone leaving and someone coming. That is just a single number substitution. How does that change the court as a whole? We need a way of aggregating the numbers.
Your first thought, if you were brought up like me would be, “it shifts the center of mass.” Since I defined zero at SDO, the center will shift by Candidate/9. So the R’s will want to make abs(Candidate) the largest number they can while the D’s will want to try to limit that number.
But why should we use the center of mass? I offered no justification for that. Does the center of mass of the court really matter? If I put Michael Savage, -6, on the court, would that be substantially different than if I put someone with a -3 instead? No. Why not? Because they don’t use votes weighted by strength of opinion (except to the degree that one justice can convince another to change opinion). They use a simple count of votes, and the majority wins. It seems that we should instead be talking about the median.
So how much can we move the median? Since, by all accounts, SDO was the median, we can pick a new one, but only if it falls between the two on either side (let’s just call them Breyer and Kennedy for convenience). So based on that, all that the R’s can do is shift the median as far as Kennedy. That implies that having someone more conservative than Kennedy is no better than having someone equally conservative as Kennedy.
But we are perhaps being short sighted. Our new guy is sure to outlast some of the others. Someone else will be in a position to move the median again. If it is the R’s again and it is someone left or center who resigns or dies, they can move it one more place to the right. In that case (and its repetition), they don’t want to have put the new guy in the way of getting the median out to Thomas. In all the other cases (13/18ths of the time, on average), it doesn’t matter how extreme a guy they pick.
I just wanted to point this out that there isn’t really a large benefit for picking someone too far from the center. But I’m guessing that Rove is thinking to himself. “Let’s start out with a real wing-nut. Make them fillibuster. Harp on them for fillibustering for a week. Then back off and give them our “moderate” conservative. They’ll accept him to save face, and we’ll look like statesmen for compromising. Wait, no. Americans don’t like compromises. I guess we can use the nuclear option and put the wing-nut on the court. The base will be really psyched about that.”
I wonder what Dean is thinking?