Jury size and the jury-voting rule have both been the subject of scrutiny by many cases before the Supreme Court and beyond. As a result of several local cases, such as Ballew v. Georgia and Burch v. Louisiana, the heterogeneity of the jury sizes has increased—spurring a subsequent increase in the academic scholarship surrounding the topic. King and Nesbit found that the cost-minimizing number of jurors was nine. Luppi and Parisi suggest that smaller juries avoid the negative effects of the informational cascade bordering on the herd mentality. In an interview with this publication, Harvard professor Kenneth Felter supported a heterogeneity of jury size across the nation, citing efficiency concerns.
The jury trial is a cornerstone of the American legal system; it allows for disputes to be settled by the peers of both the plaintiff and the defendant. Two of the main facets of trial procedure—jury size and the jury-voting rule—are of particular interest among scholars, policymakers, and Supreme Court Justices. In Williams v. Florida (399 U.S. 78 ), the Court overturned its decision in Thompson v. Utah (170 U.S. 343, 349 ), which construed the Sixth Amendment to require that in all criminal cases “a jury [be] compromised of 12 persons, neither more nor less.” In Williams, the Court ruled that the constitutionality of a limit on jury-size rested on whether such a reduction would undermine the jury’s essential function of grounding the judicial process in the “common-sense judgment of the community” (Luppi & Parisi 401).
Further, in Ballew v. Georgia (435 U.S. 223 ), the Court set a lower limit on jury size, holding that a jury with less than six members would be unconstitutional because it would be too small to be representative of the relevant community” (Luppi & Parisi 401-02). In regards to the jury-voting rule, the Supreme Court, in Burch v. Louisiana (441 U.S. 130 ), ruled that state courts are free to reduce the jury size or to modify the decision rule, but not both; thus, states cannot permit smaller juries to decide non-unanimously (Luppi & Parisi 416).
As a result of these court decisions, heterogeneity of jury sizes across the United States has increased; this heterogeneity opens the door for courts to optimize their jury size. The flexibility arising from the Supreme Court’s rulings in 1970, 1978, and 1979 has been widely supported across the United States; by 2013, 40 states allowed smaller juries in at least some misdemeanor criminal trials (Luppi & Parisi 402). Through its rulings, the Supreme Court developed a jury trial system with the flexibility for the different courts across the United States to choose the jury size that suits them best, based on the citizens in their area. In the years following these decisions, research was conducted to study the effects of the variety of potential jury sizes brought by the Supreme Court decisions. One such study, conducted by Kerry King and Todd Nesbit, attempted to find the number of jurors and jury-voting rule that would minimize the costs of Type I errors, Type II errors, and juror’s time; they found that the cost-minimizing number of jurors was nine along with a jury-voting rule of unanimity (470). If a cost-minimizing number of jurors exists, then we would want that number uniform across different states, but King and Nesbit are unconvincing; their study is based on flawed assumptions and the jury size calculated is calculated for the “average” jury. Across the United States, there are a plethora of ethnicities, religions, races, socio-economic levels, and life experiences; although a jury of 9 is best on average, some areas in the United States are far different from the “average” and could potentially benefit from, say, a jury of 10 or 6.
Barbara Luppi and Francesco Parisi find that, assuming judgments are expressed sequentially, jurors can “adjust their judgments in light of what others have expressed…. an increase in jury size increases the likelihood that by the time a dissenting juror is called to express her judgments, her voting preference will have changed in response to the judgments previously expressed by other jurors” (409). Further, they find that the larger the jury, the more heterogeneity’s effect on dissenting jurors can be diminished by informational cascades – where a person observes the actions of others and takes on the same decisions despite personal contradictions with their chosen action (414). Luppi and Parisi deduce that the informational cascade effect is weakened in smaller juries; informational cascades can have a negative effect on juries because after a certain point, no new information will be added to deliberations and jurors will tend towards herd mentality (415). Further, heightened levels of heterogeneity are more likely to produce deadlock and lower rates of correct unanimous verdicts (Luppi and Parisi 415). The flexibility of the Supreme Court’s decision allows for differently sized juries, and thus different areas of the country can benefit from a jury size that best fits. For example, all else being equal, an area with high religious, ethnic, or moral homogeneity, could benefit and cut costs from a 6-member jury because heterogeneity is not an issue. If a 6-member jury were to be highly heterogeneous, the informational cascade effect would be weak and the juror’s widely differing views would be more likely to lead to deadlock and lower rates of correct unanimous verdicts. Conversely, a highly heterogeneous area could benefit from a 12-member jury because the larger jury will mitigate heterogeneity’s effect on dissenting jurors through informational cascades.
In order to further investigate the effects the different characteristics and demographics of juries, I interviewed Professor Kenneth Felter, a current Harvard professor and retired partner at Ropes & Gray LLP. In his time as a defense trial lawyer, Professor Felter practiced widely in trials across many states. He explained that a big influence in trials takes root in the characteristics of the community from which the jury is drawn, citing an example of an eastern district of Texas were there are many patent cases filed and in which juries have been historically pro-patentee and have given large awards for damages. His example further supports the idea that a uniform jury size rule is unlikely to be as efficient as having flexibility of jury size because different areas of the country have different characteristics and demographics, and may thus benefit from a different jury size than the “average” jury in the United States.
Michelle Baddeley and Sophia Parkinson provide further proof of the benefit of a flexible jury size. In their study, they find that the strongest compromises between jurors were “in groups comprising of more strangers and acquaintances than friends” (566). This makes sense in terms of preserving relationships and avoiding future uncomfortableness among friends; a heated debate between friends is less likely to occur than unconditional agreement and herd-like behavior among friends. In a highly rural area with few residents, jurors are more likely to know each other, so a smaller jury—of, say, six—would reduce the probability of being in a jury with a friend, which would prove to be beneficial for the court.
In Professor Felter’s general experience dealing with different jury sizes, the vast majority of the juries he has worked with have been 12. The few times he worked with a 6-person jury, while he was cognizant of the differing jury sizes, he generally did not prepare differently, with the exception of the preliminary jury-selection hearing, since he had to be aware of what may influence 6 people as opposed to 12. “The facts of the case,” he said, “are what matters in the end.” When asked if he prefers a smaller or larger jury, he explained that he would prefer a smaller jury if the plaintiff had a very convincing case and a larger jury for a more difficult case. His reasoning was that, with strong evidence, it would be simpler to explain and ultimately prove his case to a smaller number of people than a larger group of people. In entertaining the idea of the existence of a cost-minimizing uniform jury size, I also asked him how achievable he thought it’d be to set a default jury size and jury voting-rule across all states. His answer was that there are many great reasons for states to have their own rules. He provided the Federalist concept of states’ rights that our country was built upon as an example. I would certainly agree with Professor Felter, as the arguments for allowing flexibility of jury size across states have provided me with a new appreciation and understanding for the need of states’ rights. He went on to further explain that setting a default jury size and jury voting-rule across all states would be extremely difficult to implement, as each state has its own traditions, laws, and rules.
In Williams v. Florida (399 U.S. 78 ), the Supreme Court interpreted the Sixth Amendment to allow for jury sizes smaller than twelve as long as the smaller juries continue to contain the representativeness of a community. Through studies on jury sizes and the interview with Professor Felter, it is apparent that the flexibility provided by the Court allows for areas with different characteristics around the country to utilize the jury size that fits best. The jury trial procedure was created to protect citizens and it is one of the oldest rights provided by the United States. A proper jury trial system should be both fair and efficient, and a uniform jury trial system across the United States would fail to recognize that the United States is not a homogenous nation. The people and areas across the United States are fairly heterogeneous, so the flexibility provided by the Supreme Court’s decisions allows for the continued protection and fairness of the right to a jury trial.