Statistical Measures and Methods for Assessing the Representativeness of Juries: A Reanalysis of the Data in Berghuis v. Smith

Abstract

This term the U.S. Supreme Court will decide Berghuis v. Smith; a case concerning the criteria a defendant claiming that the jury pools in a jurisdiction are not representative of the community must meet to establish a prima facie case. Many courts consider the arithmetic difference between the percentages of minorities in the age-eligible population and on a number of jury venires; the Sixth Circuit relied on a relative measure, the ratio of the arithmetic difference to the minority fraction of the age-eligible population. The data for the period when the defendant’s trial was held indicate that 6.03% of the potential jurors in the circuit (felony) courts were African-American but they formed 7.28% of the age-eligible residents of the County. Under the absolute difference criteria, the 1.25% figure seems small. The comparative difference or percentage shortfall is 18%, which suggests underrepresentation. The data will also be examined using the selection ratio and formal statistical testing as in Castaneda v. Partida. The available data in Berghuis v. Smith differs from most jury discrimination cases as the source of the master list did not keep racial identification nor did the county record the race of the individuals summoned. The defendant’s expert estimated the number of African-Americans on the venires from their addresses and compared it to their expected number derived from their fraction of the county’s age-eligible population. He did not conduct a formal statistical test to assess whether the difference was statistically significant. The federal appeals court found that African-Americans were underrepresented on the juries in the county’s circuit courts. At the time of the trial jurors were first assigned to local courts and as African-Americans were concentrated in Grand Rapids, this could have lead to their underrepresentation of minorities on the circuit court. Although the Sixth Circuit agreed that some hardship excusals for child care needs were legitimate, it did not accept that they would fully explain the degree of underrepresentation of African-Americans. The Census data on sole heads of poverty households, with a young child, not mentioned by either party, indicates that if most requested to be excused for child care responsibilities, a good part of the disparity might be explained. On the other hand, using the correct standard deviation analysis for the statistic used to compare the expected percentage of African American venire members to their percentage of the age-eligible population yields a statistically significant disparity meeting the two standard deviation level for the first time period, the three standard deviation level for the second time period and is nearly four standard deviations for both. Thus, the Court will be deciding a very important issue of fairness on the basis of a statistical record that has not been carefully analyzed.