4.The Boys in the Bubble This is the theory used to explain David Souter's dramatic defection from solid conservative preconfirmation to reliable liberal justice. The argument is that he had so little "real-life" experience prior to his confirmation that he only developed his jurisprudential views after donning the black robe. Souter himself has said that when he was confirmed he knew next to nothing about important federal constitutional issues—having had experience as a state attorney general and then as a state supreme court justice. At his confirmation hearings he answered truthfully but saw his views change radically once he began to truly study the issues. Because judges often hail from Ivy League institutions or from the lower courts, they may be less likely to have fully formed political ideologies. Certainly there is some truth to the proposition that justices who either rose through the executive branch (like a Clarence Thomas) or had tremendous advocacy experience (like a Ruth Bader Ginsburg) are less likely to change their views once confirmed.
5.The Law Is a Moderate Mistress This theory holds that there is something inherently moderating about the law itself; that the traditions and pace of the legal system tend to foster centrism and moderation. The "drifters" of the Supreme Court world—the Kennedys and O'Connors—are not so much evolving toward the left, therefore, as they are evolving toward the center.
This theory explains why Stephen Breyer has similarly moved rightward, proving to be the swing vote in this term's blockbuster case allowing displays of the Ten Commandments on state grounds, and joining the court's conservatives in matters as vital as the presidential power to detain enemies in wartime. We don't hear much from the media about Breyer's occasional defections to the conservative team, and certainly liberal pundits don't call for his impeachment the way Phyllis Schlafly does each time Justice Kennedy strays from the reservation. But it remains true that strong centripetal forces on the court tend to pull everyone slightly toward the middle. *
What does all this say about the likelihood of a John Roberts "evolution" to the left? Rank speculation suggests that he may drift somewhat, but not a whole lot. Roberts' intellectual confidence points to a man unlikely to be swayed by the siren song of the opinion pages, and his ability to get along with everyone suggests that he may not only withstand Scalia's barbs but could assume the role of leader of the conservative wing—attracting moderates like Kennedy and Breyer back to the fold. Roberts' extensive experience in the executive branch and his role as successful advocate for conservative positions means he likely has a well-thought-out judicial philosophy on hot-button issues like abortion and gay marriage, and that, unlike Souter or O'Connor, he won't be crafting his views as he goes. Roberts is also a deeply religious man, which may keep him from sliding toward the center the way Scalia and Thomas have resisted the pull.
But, unlike Scalia and Thomas, Roberts seems to recognize the fundamental role and value of moderation in the law. He respects its glacial pace and tends to understand that his job is to guide, not shape, the law. In short, Roberts may shift toward the middle over time, but he is highly unlikely to become the court's staunchest liberal. However, 30 years is a long time. And Linda Greenhouse is most charming.