"... by the way, biological proclivity to violence is a mitigating factor rather than an aggravator factor?" -- Justice Scalia (38:9-11)
The transcript of argument in Schriro v. Landrigan is available here. It's a rather confused argument, and Justice Kennedy notes early on (5:11-14) that he thinks the parties have been talking past each other. The most outrageous part of this case, from the prosecution viewpoint, is that the Ninth Circuit overruled a state court factual finding that the defendant had waived presentation of mitigating evidence. It did so based on its reading of the record, despite the fact that the contrary finding was made by the original trial judge. The defense today essentially conceded that was indefensible and now asks that the issue of whether there was an effective waiver be one of the issues to be considered in the district court on remand (pp. 34-36).
The actual holding of the state trial judge in this case was that, “defendant instructed his attorney not to present any evidence at the sentencing hearing. . . . ” (emphasis in original). Even so, there was much discussion about whether defendant would have allowed other kinds of mitigation evidence that the lawyer could have but did not prepare to present. If seemingly unequivocal state court findings can be danced around so easily, why have state habeas proceedings at all?
This one is difficult to assess from the argument. No predictions.
P.S. None of this mitigation argument would matter if we could just decide as a matter of law that a previous murder necessarily outweighs any mitigation. But the Supreme Court unwisely barred the states from doing that in Sumner v. Shuman, 483 U.S. 66 (1987).