Hanging the Jury: Social Psychology and the Integrity of the Jury System

            In the vast majority of states, criminal juries must reach a unanimous verdict. When they fail to do so, judges can sometimes give what is known as an Allen charge, which encourages dissenting jurors to reconsider their opinions, though some state courts have rejected the Allen charge. Recently, it feels as if hung juries are all over the news – from Tennessee to California. Why is it, however, that juries from Michigan to Oklahoma are occasionally unable to reach a unanimous verdict, and what does that mean for our criminal justice system?

            A variety of factors change the likelihood that any one jury will be hung, from case clarity to jury size (though the effect of jury size is complicated) to deliberation style (juries that use secret polling hang more often than juries that poll by open voting) to the initial impressions of the jurors (larger minorities hang onto their opinions easier). The conduct of the foreperson can even impact the jury’s findings: forepersons in unanimous juries in experimental settings have been shown to direct deliberations toward the evidence more than forepersons in hung juries. The same study found that, sometimes, the Allen charge gets it wrong, and it is the majority of the jurors who are resistant to changing their minds in light of the evidence.

However they come about, hung juries result in systemic questions. When a jury is hung, prosecutors almost-unanimously assure the media that they will retry the case. United States v. Perez is cited to sanction that retrial, though concerns exist over whether Perez actually stands for the constitutionality of that retrial, particularly in light of the body of law that has been developed regarding double jeopardy. The option to retry the case raises a question about how we interpret “reasonable doubt” in criminal cases: if a jury of twelve people were unable to agree as to the defendant’s guilt, doesn’t that imply that there is a reasonable doubt that the defendant may not be guilty? Or is a hung jury simply a product of jurors being unreasonably resistant to considering the evidence before them?

And what do we make of the concern that the Allen charge may reinforce the beliefs of intransigent majorities who cling to an initial feeling of rightness without considering the evidence? Alternatively, does the Allen charge simply encourage jurors to go along with a majority they conscientiously believe to be wrong, and thus undermine the integrity of the deliberations? These questions do not have easy answers, but they are discussed extensively by psychologists and jurists, with an eye for balancing the efficiency of the jury system with its integrity.

Even with these concerns, however, hung juries highlight the importance of juror conscience in our jury system, and the risk of a hung jury should not necessarily be considered a flaw: in fact, a hung jury provides an opportunity for prosecutors to re-examine the strengths and deficiencies in their case, and highlights for jurors the integrity of the jury system. For prosecutors, a hung jury may raise questions about whether they have adequately proved their case, and if a retrial is permitted, may give the prosecutor the ability to put on a more comprehensive or persuasive showing of the evidence. For defendants, a hung jury again highlights the flaws in the prosecution's case, and may provide a roadmap for a more vigorous defense in a retrial. For jurors, the hung jury is proof that the system is based in the human conscience, rather than being rigged for one side or the other. For all sides, then, the hung jury provides security and, perhaps, an opportunity.