Asking the nominee to critique past cases is as legitimate as asking a job candidate to imagine how he or she would have handled situations that faced employees in the past. After all, a justice's job is to decide and explain cases, while a nominee's job is to give senators information about the kind of justice he will most likely be. The nominee's candid assessments of previous decisions are similar in kind to the written opinions, dissents, law review articles and speeches from which a sitting justice's record can be examined, and that is exactly the sort of material the Senate needs in order to make a fair and well-informed decision.

Update (TL): Eric Muller at Is That Legal has a question for Roberts.

Second update: Another question for Roberts: Do you really believe the constitutional right to habeas corpus makes "a mockery of the entire criminal justice system"?

One issue Roberts focused on [when he served in the Justice Department during the Reagan administration] was appeals by prisoners, who in the 1980s had several avenues of challenging their sentences in both state and federal courts. Since then, courts generally have limited prisoners' options, with justices this past term clashing over how closely they should scrutinize death penalty sentences by state courts.

The availability of federal court appeals, "particularly for state prisoners, goes far to making a mockery of the entire criminal justice system," Roberts wrote in a Nov. 12, 1981, memorandum, decrying the endless appeals that "obscures the rare serious claim."