Jim Lindgren of the Volokh Conspiracy has an interesting post examining what sorts of nominees ultimately end up drifting to the left once they’re on the court. He looks at Republican court appointees since Eisenhower, who famously nominated the men he called his two greatest mistakes, liberal judicial heroes Earl Warren and William Brennan. Likewise, Richard Nixon appointed Harry Blackmun, Ford appointed John Paul Stevens. Reagan appointed O’Connor and Kennedy, both moderately conservative but not the sort of ideological conservatives like Thomas and Scalia that the right hopes for.
The only two who haven’t disappointed conservatives greatly during that time are Scalia and Thomas. And Lindgren points out what set them apart before they were nominated:
Yet since the Stevens nomination, the only two Republican-appointed Justices who stayed fully true to form were Scalia and Thomas. Consider how these two differed from the other Republican appointments over that period (Stevens, O’Connor, Kennedy, and Souter). Scalia and Thomas were movement conservatives who before their nomination were publicly attacked for their views. Before appointment, they had taken public positions that were perhaps broadly popular with the general public, but unpopular with educated elites and the press. Scalia and Thomas had sharpened and defended their ideas against attack.
By contrast, before their nominations Justices Stevens, O’Connor, Kennedy, and Souter had not faced much public criticism for their judicial and legal ideologies. Their conservative ideologies were not as well formed, if they existed at all. Thus, they “grew in office.” In her conservative background before appointment, Miers is much more like O’Connor, Kennedy, and Souter (and Blackmun from an earlier era) than like Scalia and Thomas.
I reiterate what I said before: for those liberals in the Senate, and their supporters, who care only about outcomes and not having the court shift to the right in the wake of O’Connor’s retirement, your best bet is to get behind Miers fully and confirm her. She really is far more likely to drift to the left on the court than almost anyone the President might nominate in her place if her nomination is withdrawn due to opposition. A Luttig or McConnell is much more likely to be consistently conservative because, like Scalia and Thomas, their views have been forged in public battle with other legal scholars. If your concern is having the best legal minds we can find on the court, as I am, this probably seems like a bad idea. But as a matter of practical politics, it makes perfect sense.