STANFORD, Calif.- LAWFUEL – Legal News Network –Remember when, in t…

STANFORD, Calif.- LAWFUEL – Legal News Network –Remember when, in the second half of 2005, the U.S. Supreme Court was the subject of intense media scrutiny surrounding the impending retirement of Justice Sandra Day O’Connor and the death of Chief Justice William Rehnquist? Journalists and political analysts alike debated the impact that these two vacancies and the resulting judicial appointments would have on the politics of the court, while the public watched uneasily.

But not Keith Krehbiel, professor of political science at the Stanford Graduate School of Business. Seeking a more logical, fact-based answer to the question, he initiated a study to determine under what conditions executive appointments to the court would have an immediate bearing on policy. “There was a lot of alarmist press and punditry about how this would tip the court in a radically conservative direction,” Krehbiel recalls. “As a political scientist, I’m always on guard for ideological claims that are not rationally defensible. And I had a suspicion that these claims were overstated.”

Krehbiel argues that no single appointment can have a truly profound, immediate effect on the politics of the court because of the complex conditions required to move the median vote by a member of the court to a more conservative or liberal position. While he concurs with other observers that appointments have important consequences on public policy in the aggregate and over the long term, Krehbiel maintains that the average appointment opportunity is of limited consequence to short-term policy outcomes.

Applying his expertise in game theory and collective choice, Krehbiel analyzed four decades of Supreme Court appointment data for his research. Central to Krehbiel’s study is the idea that within the court, as within any institution that exercises collective choice, there is a median (the voter for whom half the other voters are to his right and the other half are to his left in terms of the conservatism or liberalism of their views). The median acts as a strong gravitational force in decision-making, since no given policy can command majority support without winning the median voter’s support. Once adopted by a ruling and majority opinion, the court’s median policy is difficult to move, as Krehbiel explains, “because a majority can’t be put together to move it left, and a majority can’t be put together to move it right.”

When court vacancies arise, the president has a potential opportunity to “move the median,” but only when specific conditions are met. First, the views of the vacating justice and the president must be on opposite sides of the median (otherwise, any new appointment that the president would wish to make will serve only to maintain the status quo). Second, the pivotal voter in the Senate also must hold views on the same side of the median as the nominee in order for the nomination to be confirmed.

According to Krehbiel’s study, “Most of the time, at least one necessary condition for moving the median fails.” And, he continues, “Even when both conditions are met, the magnitude of change is tightly constrained by the median voter’s nearest ideological neighbor.” What this means is that if, for example, a new justice joins the court to the right of the established median, the new median will shift no farther than the justice with the voting record closest to the previous median voter — albeit slightly to the right. The change in policy is constrained to an incremental move.

As a result, says Krehbiel, “The conditions for a single Supreme Court appointment to be cataclysmic are basically never going to be met. …In roughly half the cases, a Supreme Court appointment analytically will not change policy at all. And in the other approximately half of the cases when it will change policy, it will change policy only a little bit.”

Applying Krehbiel’s model to the Supreme Court appointment opportunities in the summer and fall of 2005 not only helps illustrate his point, but sheds light on the debate that raged in the press during this period. The appointment of John Roberts to replace William Rehnquist resulted in the preservation of the status quo, since Rehnquist’s voting record was squarely to the right of the established median and Robert’s ideological views were directionally aligned with Rehnquist, as well as with the president and the Senate.

O’Connor’s replacement, on the other hand, was slightly more interesting, as Krehbiel puts it, “because people said, ‘O’Connor is the swing voter and replacing the swing voter with a conservative will radically tip the court.’” In reality, however, the effect of the change is likely to be limited. “As it turns out, Anthony Kennedy and Sandra Day O’Connor had virtually identical voting records, with Kennedy very slightly more conservative than O’Connor,” says Krehbiel. “So, regardless of how conservative her replacement [Samuel Alito] is, it’s only going to move the median a trace.”

Summarizing the central finding of his study, Krehbiel says, “The punch line is that any given appointment doesn’t matter very much.” However, he acknowledges that the long-term implications of successive appointments by a single political party can be significant. “In the longer term, no one would say that the composition of the court is irrelevant in American politics. Over the course of two- or three-decade periods, it is not uncommon to observe slow but significant swings in the court’s composition.” Referencing the 10 uninterrupted appointments to the Supreme Court made by the Republican Party under Presidents Nixon, Ford, Reagan, and Bush Sr., he says: “From 1969 to 1992, a considerable amount of conservative drift occurred because incremental changes added up. But the ideological pendulum swings both ways. So, considered in the broader historical context, the theory suggests that the court’s contribution to public policy eventually will inch back toward more liberal policies.”

How soon might we expect this? “That’s easy,” replies Krehbiel. “Not soon. The theory makes it clear what has to happen. First, Democrats must win a string of presidential elections. Second, retirements from the court have to occur disproportionately from the conservative wing to create several opportunities for left-of-center presidents to move the median. Third, the Senate must give consent to the presidents’ nominees.

“Notice, however, that even if Democrats are somehow able to reverse their recent electoral misfortunes, the demographics of the present court are not in their favor. The three justices under 60 — Roberts (51), Alito (56), and Thomas (58) — are among the most conservative, and they can be expected to stick around a long time. Meanwhile, the two oldest justices — Stevens (86) and Ginsberg (73) — are most liberal by most measures. If, as is likely, the seniors retire or, let’s say, ‘involuntarily vacate’ before the juniors, then a successful Democratic appointee will not move the median at all. In contrast, if the seniors were somehow to outlast the juniors, a successful Democratic appointee will move the median only a slight amount — in the first instance, for example, from Kennedy to Breyer.”

As for broader implications of this and previous research by Krehbiel, he concludes, “Separation-of-powers and shared-powers systems such as ours do some things very well. Passing durable, moderate policies is one of them. However, achieving immediate and ideological judicial policy responses to electoral forces — even large ideological electoral forces — is not one of them.”

(This story reports on research at the Stanford Graduate School of Business and appears in today’s Stanford Knowledgebase, the free monthly information source for thoughts, ideas and lectures at the Stanford Graduate School of Business. For related research citations and to dig deeper, visit

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