As Kent has explained, California requires a penalty phase retrial when the jury fails to agree unanimously on the sentence, and does not limit the number of retrials. See People v. Trinh, 59 Cal.4th 216, 237-239 (2014) (applying Cal. Penal Code, Section 190.4(d), and upholding the constitutionality of the statute. Alabama also allows a new jury capital sentencing proceeding if the jury deadlocks and allows 10 of 12 jurors to recommend a death sentence. Ala. Code 1975, Section 13A-5-46. However, under Alabama law the jury's sentence is merely advisory to the court because the court may impose a death sentence even if the jury recommends a prison sentence. See Harris v. Alabama, 513 U.S. 504 (1995) (upholding the Alabama law and the state court's decision to impose the death sentence against the contrary recommendation by the jury). The Kentucky Supreme Court has held that the failure of the jury to unanimously agree on the sentence in a capital case or in a persistent felony offender case requires a penalty phase retrial until a jury agrees to a sentence, unless both parties waive that procedure. See Skaggs v. Commonwealth, 694 S.W.2d 672, 681 (Ky.1985) (rejecting the argument that life sentence must automatically be imposed when the jury fails to unanimously agree on the sentence and ruling that a penalty phase retrial after a hung jury penalty phase mistrial is constitutional). See also Sattazahn v. Pennsylvania, 537 U.S. 101 (2003) (holding that the failure of the jury to agree on a penalty verdict is not an acquittal of the aggravating circumstance or the death penalty).

The Kentucky Supreme Court and Ohio Supreme Court have upheld asking potential jurors whether they would be willing to sign a death sentence verdict once the jury made the required findings of guilty and agreed to a death sentence. See Hunt v. Commonwealth, 304 S.W.3d 15, 41-42 (Ky. 2009), citing State v. Davis, 116 Ohio St.3d 404, 880 N.E.2d 31 (2008) (upholding asking a similar question about the willingness of a potential juror to sign a death sentence verdict since Ohio requires all 12 jurors to sign the verdict). That question has been very helpful as a tool to exclude jurors who are willing to "consider a death sentence" but who would never vote for it in any case because many will explain that they could never sign a death penalty verdict under any circumstances. Unfortunately, there are some potential jurors who interpret "consider" as meaning to listen to the evidence and arguments and automatically vote against any death sentence in any case because they view "consider" as simply meaning to listen with no possibility of ever voting for a death sentence. I suspect that the hold out juror in the Jodi Arias case in Arizona fell into that category.

Another problem is that the one juror death sentence veto law has been employed to reduce the degree of prejudice that a convicted defendant must show when claiming ineffective assistance of counsel in the penalty phase. See Wiggins v. Smith, 539 U.S. 510, 537 (2003), citing Maryland ruling, Borchardt v. State, 367 Md. 91, 139-140, 786 A.2d 631 (2001); Maryland Code, Criminal Law, Section 2-303(j)(2) (repealed when the Maryland Legislature abolished the death penalty). Wiggins v. Smith explained that the particular ineffective assistance of counsel prejudice standard that measures prejudice as whether counsel's failure to present evidence could have influenced a single juror to vote against the death sentence was employed in that case to conform to state law that adopted the single-juror veto rule for capital sentencing and the state high court ruling that adopted that prejudice standard. However, Justice Sotomayor has written two dissenting opinions relying upon Wiggins v. Smith to argue that standard must be applied to California and Kentucky even though both of those States did not adopt a single-juror veto law. Cullen v. Pinholster, 131 S.Ct. 1388,1430 (2011)(Sotomayor, J., dissenting); Hodge v. Kentucky, 133 S.Ct. 506, 508 (2012) (Sotomayor, J., dissenting from denial of cert.). She possibly made that argument because counsel for those States in those cases failed to explain that those States do not have a single-juror veto law. However, her dissenting opinions can also be read to impose the single-juror veto ineffective assistance of counsel prejudice standard in every State that requires a unanimous jury sentence verdict regardless of whether that state has adopted the single-juror veto rule, i.e., even in those States that require retrials until there is a unanimous jury verdict. This issue is yet another reason to reject any type of single-juror veto rule or unanimous jury verdict rule regarding capital sentencing.