Did chief justice misuse statistics to make a point on the Voting Rights Act?
The New York Times blogger and statistical whiz who correctly predicted President Obama’s re-election success has a bone to pick with Chief Justice John G. Roberts Jr.
At issue is a comment by Roberts during oral arguments last week on the constitutionality of preclearance requirements in the Voting Rights Act. Under Section 5 of the law, states and jurisdictions with a history of discrimination are required to get advance approval of voting rights changes. Roberts said that Massachusetts, which is not covered by the law, “has the worst ratio of white voter turnout to African-American voter turnout,” the New York Times reported at the time. Mississippi, on the other hand has the best ratio, the chief justice said.
Writing at the New York Times blog FiveThirtyEight, Silver says Roberts appeared to be citing 2004 census bureau data referenced in a lower court brief. Those statistics found that white voter turnout in Massachusetts was 72 percent while black turnout was a much lower 46.5 percent. In Mississippi, on the other hand, white voter turnout was 60.2 percent and black turnout was a higher 66.8 percent.
But Roberts focused on two states without looking at broader trends, Silver says. The blogger charted 2004 voter turnout data in all the states that are subject to the preclearance requirement and those that are not. Differences in white-to-black voting ratios between the two sets of states are so small, Silver says, that they are not “meaningful in either a statistical or a practical sense.”
“So did Chief Justice Roberts misconstrue the data?” Silver writes. “If he meant to suggest that states covered by Section 5 consistently have better black turnout rates than those that aren’t covered by the statute, then his claim is especially dubious. However, the evidence does support the more modest claim that black turnout is no worse in states covered by Section 5.”
The bigger flaw in Roberts’ argument, Silver concludes, is his suggestion that an increase over the years in black voter turnout in Section 5 states is evidence that the law is unnecessary. Perhaps the statistics mean the law has been effective, Silver says.
“As much as it pleases me to see statistical data introduced in the Supreme Court,” Silver writes, “the act of citing statistical factoids is not the same thing as drawing sound inferences from them.”
Hat tip to How Appealing.
