Although a simple Google search would likely have revealed the impeachment evidence against the defense expert witness in a capital case, not investigating the witness beyond a reasoble reliance on the judgment of the professional commnity was not ineffective assistance of counsel.
Petitioner wasn't prejudiced by lack of replacement psychologist's testimony, a witness who would have provided evidence on an aggravating factor on which the jury ended up not being able to reach a decision, since from a legal point of view the testimony would have been duplicative of the overwhelming evidence on this point; there was therefore not a substantial likelihood of a different result.
AEDPA deference to state habeas finding to the contrary offers an independent ground for overruling the district court ruling that petitioner was prejudiced by the lack of testimony.
Since the ineffective assistance claim wasn't substantial, petitioner can't raise it in federal habeas after defaulting in state habeas, since excuse of default requires a substantial claim.
While jury instructions can't require that a jury be unanimous on any one mitigating factor, they can require that the jury be unanimous in its decision that the mitigating factors outweigh the aggravating factors.
District Court erred in holding that the weighing of mitigating and aggravating circumstances was a finding of fact upon which the legislature had conditioned an increased punishment and that therefore must be performed by the jury, since the supreme court of the state has held in this case that the same precedent referenced by the district court was inapplicable.
CONCURRENCE:
Although the investigation of the expert witness was insufficient, there was no prejudice, given the other evidence offered.
State supreme court has held that only the existence of a single mitigating factor need be found by the jury under the statutue, as it constitutes eligibility for the increased sentence.
http://media.ca8.uscourts.gov/opndir/21/08/183510P.pdf
