Deeper thoughts on Marsh and sentencing burdens of proof

As detailed here, my first reaction to today's cert. grant in Kansas v. Marsh was "blah...another capital case."  Fortunately, fellow Prof. Adam Thurschwell had deeper substantive insights on Marsh, since the case raises the interesting question of whether it is constitutionally acceptable for a state to require a jury to rule for death if it finds the aggravating and mitigating circumstances evenly balanced.  Upon my request, Adam has allowed me to share his insights here:

It seems to me that the Court may have foreshadowed its view in the recent Deck v. Missouri case (visibly shackled defendant during DP penalty phase violates due process), where, by analogy with the effect of shackling on the presumption of innocence, the Court said of the penalty phase decision,

Although the jury is no longer deciding between guilt and innocence, it is deciding between life and death. That decision, given the " 'severity' " and " 'finality' " of the sanction, is no less important than the decision about guilt.  Monge v. California, 524 U.S. 721, 732 (1998) (quoting Gardner v. Florida, 430 U.S. 349, 357 (1977)). . . . . . Neither is accuracy in making that decision any less critical. The Court has stressed the "acute need" for reliable decisionmaking when the death penalty is at issue.

I am wondering if this language can be squared with the Kansas statute.  They're probably distinguishable, but the closest analogy would seem to be the cases on due process limitations on the burden of proof for various issues, e.g., Medina v. California (OK to require defendant to proved by preponderance that s/he's incompetent) and Oklahoma v. Cooper (not OK to require defendant to prove by clear and convincing evidence that he's competent).  Given the language from Deck, the life/death decision sounds much closer to In re Winship, which emphasizes how the BARD standard is designed to implement the presumption of innocence.  This issue (and the potential Winship analogy) is important beyond the Kansas statute (which is unique to my knowledge, but I'd be interested in hearing otherwise), by the way, because the federal death penalty statute (and many state statutes as well, I believe) do not require juries to find that death is the appropriate sentence BARD; instead, they generally require that the individual aggravators be found BARD. The jury gets no burden of proof instruction at all on the ultimate life/death finding.

I am spotlighting Adam's insights not only because of the interesting Deck connection, but also because he rightly spots that Marsh might be a vehicle for the Supreme Court to speak more broadly to issues relating to the burdens of proof at sentencing — issues which, as stressed in my most recent Blakely/Booker article, I think are of critical future importance.  Consequently, I suppose I should not be so grumpy about the Supreme Court taking up Marsh.