"We've been idling many years with the court being noncommittal."

AP's Gina Holland quotes me in this analysis of how Alito's replacing O'Connor might change the Court:

The Supreme Court's middle ground is disappearing. If Samuel Alito is confirmed, he could almost immediately begin to erase the court's balanced rulings on contentious social issues like abortion, religion and capital punishment.

With pragmatic Justice Sandra Day O'Connor as its pendulum, the court has staked out moderate positions, often in line with public opinion but not necessarily clear-cut.

"We've been idling many years with the court being noncommittal," said Ann Althouse, a law professor at the University of Wisconsin.

That is likely to end with Alito, who is expected to bring a more reliably conservative approach to areas that O'Connor has influenced: abortion restrictions, the death penalty, campaign finance, affirmative action and states' rights.

The shift could be abrupt....

O'Connor sometimes votes with Scalia and other court conservatives, and other times provides the fifth vote to the court's more liberal wing....

Another room for change is the area of states' rights. Alito, like Scalia, is expected to side with states more often in power struggles with Congress.

While O'Connor has generally been a strong states' rights advocate, her vote is not guaranteed. Last year she was the swing vote in a 5-4 ruling that said disabled people can sue if states ignore a civil rights law on access to courthouses....

In her 24 years on the bench, O'Connor has been known for pragmatic votes, like her tie-breaking 2003 vote to allow limited affirmative action in college admissions.

"Because of her style of interpretation, you could never tell whether she was gauging the political preferences of society ... reaching outcomes that were good in a policy or political way," said Althouse, at the University of Wisconsin. "People would criticize her as being mushy."

With Alito, there will be less flexibility, which would please lawyers but may disturb some people, said Althouse.

Let me expand a little. I don't know what sorts of outcomes Alito would reach, and I think that it is difficult to extrapolate Supreme Court behavior from lower court decisions, but I think O'Connor has been very much the sort of judge who looks at the totality of the circumstances and weighs all the factors. Though her vote has been decisive on frequent, momentous occasions, it hasn't said that much about what would happen in the next case, in a new context. This has left a lot of doctrine in a "mushy" or "noncommittal" state. If her replacement is willing to resolve cases in a crisper, more rule-based manner, doctrine could firm up quickly. (Which would only please some lawyers, I hasten to say!)

But will there be a majority to nail down doctrine in a lot of the areas that have been left flexible during the O'Connor era? Even assuming he becomes a reliable conservative vote, he will need more than Justices Scalia and Thomas to make a majority. What will Chief Justice Roberts and Justice Kennedy do? Justice Kennedy has already shown a tendency to stay in the middle, and I think Roberts is something of a pragmatist.