Slatearticle - why do judges move to the left?
1. They want to please the liberal elite press. *scoff*
2. Scalia is a jerk, so people vote against him.
3. The liberal view is more persuasive after years of experience.
4. They did not have solid views before coming to the court (must be combined with 3).
5. Justicies moderate their views over time.
There is little or no movement to the left. (But I don't dismiss 2-5 above.)
Lets say there is only one issue for the Supreme Court to decide: the temperature in their conference room. Each year they can change it only 1/2 degree (it is a slow moving institution). The Conservatives like it cold, the Liberals like it hot. They vote either to increase or decrease the temperature. If temperature starts out as 74 and the each current members prefers -- 58, 60, 65, 68, 69, 70, 71, 75, 79 -- slowly the temperature of the room will go down until it reaches 69. Two of the Justices will switch their votes over the years from being Conservative to Liberal. And pundits will exclaim, “How they changed!”
Justices rarely contradict their earlier opinions (not to say opinions are always rational consistent or logically coherent): O'Connor was the only Justice to vote to uphold a law against sodomy in Bowers v. Hardwick then vote to strike down a law against homosexual sodomy in Lawrence v. Texas. However, she did so not under the Due Process Clause, as the rest of the majority did, but under the equal protection clause. She did not contradict her earlier vote, her rule would be: it is okay to enforce a law against sodomy, but it must be applied equally with respect to gender.
People fooled into thinking Justices change over time in part because the court usually has a majority opinion written with stronger language than is necessary, or is interpreted more broadly -- by lower courts, the dissenting opinion, and the media -- than it actually is. Take the recent Kelo case, which held that a state government may take property, after paying fair market value, for private development that will increase jobs and taxation revenue in an otherwise stagnant local economy. Many fear this will lead to corrupt takings of any property for any development (indicating little confidence in democracy to protect landowners). A group of publicity whores has attempted to take Justices Souter's house simply to spite him. But, reading the Court's opinion closely, the fifth vote, Kennedy, made it clear that evidence of corruption of favoritism would make a taking unconstitutional (And taking a property as a means of political retaliation is unlikely to upheld by any court).
Kelo was seen as expanding the governments ability to take property, even though the government could do it before. A future decision that distinguishes Kelo will be seen as cutting back on Kelo when, in fact, Kelo never was never very extreme. When Kenndy rejects, in a future case where a local government takes one persons land, who wanted to develop homes, to sell to another developer, who also wants to develop homes, people will act surprised. They shouldn't be.
Added link: David Strauss adds substance. He argues: Presidents often appoint a Justice to deal with the issue of the day (say, FDR and economic regulation by Congress), but then disagree with the President's preferences when other areas of the law enter the headlines. Second, he points out that true "liberals" on the Court, such as Brennan and Marshall, are clearly to the left of moderate Conservatives Stevens and Souter.
Court watchers naturally come to think of the middle swing vote as "moderate" and an opinion to the left is liberal, but when you have 7 republicans on the Court, the split is between moderate Conservatives (Stevens, Souter, O'Conner, Kennedy) and hard-line - nowhere near mainstream - Conservatives (Scalia, Thomas).
It might also simply be a good political stategy to call Conservative judges liberal. By convincing TV's pundit class of this, it moves the debate (the set of opinions deemed in reasoanble dispute and allowed airtime) to the right. Conservative groups have done an excellent job on this with respect to evolution, getting the NYTimes to cover creationist babble uncritically.
Now, any Justice that gives the power to control one's own body to a limited degree (you can have an abortion, without financial aid, not in a government hospital, after walking past people screaming at you, after being read government propaganda against abortion, after going back home to wait two days, and sometimes after you get a court order you are mature enough) is labeled liberal.