Thaler v. Haynes, USSC No. 09–273, 2/22/10 (per curiam)
Nothing in Supreme Court caselaw clearly requires “that a demeanor-based explanation for a peremptory challenge must be rejected unless the judge personally observed and recalls the relevant aspect of the prospective juror’s demeanor.” In other words, there’s no requirement that the judge have been present during jury selection in order to evaluate a Batson claim defended by the prosecutor as based on the juror’s demeanor. “Thus, where the explanation for a peremptory challenge is based on a prospective juror’s demeanor, the judge should take into account, among other things, any observations of the juror that the judge was able to make during the voir dire. But Batson plainly did not go further and hold that a demeanor-based explanation must be rejected if the judge did not observe or cannot recall the juror’s demeanor.”
This holding merely applies the finely-meshed screen of habeas review, which in the first instance requires that the claimed applicable principle be “clearly established” else it can’t be applied. A state court is free to require as a matter of state (or, for that matter, federal constitutional) law that on a demeanor-based Batson defense the judge actually have been present.