The U.S. Census Bureau said Wednesday that it's on schedule to deliver the numbers used for redrawing congressional and legislative districts by mid-August after federal judges rejected a challenge that could have delayed the data release even further.
The panel of three federal judges on Tuesday denied the state of Alabama’s request for a preliminary injunction to halt the Census Bureau from using a statistical method aimed at keeping people’s data private in the redistricting numbers. The decision in federal court in Opelika, Alabama, allows the Census Bureau, for now, to proceed toward its goal of releasing the redistricting data by Aug. 16.
Alabama and three Alabama politicians had sued the Census Bureau, arguing the method known as differential privacy would produce inaccurate data. But the judges said it was too soon to pass any judgments since the numbers hadn't yet been released.
“It may very well be that the individual plaintiffs will return here once the final redistricting data are actually delivered to the states," the judges wrote. “But we cannot know whether differential privacy will inflict the harm alleged by the individual plaintiffs until the bureau releases a final set of redistricting data."
The federal judges dismissed counts brought by Alabama that argued the method would produce inaccurate data and was unconstitutional. The state of Alabama and the politicians argued in the lawsuit that the Census Bureau violated proper decision-making rules when coming up with differential privacy, and the judges allowed those counts to move ahead.
Bureau officials had said that the release of the redistricting data, already postponed from an earlier March 31 deadline because of the pandemic, would be held up for several more months if they were required to employ an alternative method to protect privacy. The delay has sent states scrambling to change redistricting deadlines or contemplate using other data to redraw political districts.
“We note the court’s ruling and will proceed accordingly," the Census Bureau said in a statement.
Differential privacy adds intentional errors to the data to obscure the identity of any given participant in the 2020 census while still providing statistically valid information. The Census Bureau says more privacy protections are needed than in past decades as technological innovations magnify the threat of people being identified through their census answers, which are confidential by law.
Civil rights group have raised concerns that differential privacy could hamper voting rights enforcement and make it harder for the creation of districts where racial or ethnic minorities are the majority.
If you picture the privacy tool as a dial with lower settings offering the most privacy and higher settings providing the most accuracy, the Census Bureau dialed up the accuracy in final guidelines issued earlier this month. The statistical term for this dial is “epsilon,” and the bureau settled on an epsilon of 19.61, significantly higher than where the dial was set in earlier test versions that critics raised concerns about.
In a statement provided by the state's legal team, Alabama Attorney General Steve Marshall said they were disappointed by the decision but would decide how to proceed after the redistricting data is released in August. The judges' ruling failed to answer if redistricting data must be based on the actual head count produced during the once-a-decade census and if the “unprecedented level of error" the Census Bureau plans to inject into the data is lawful, Marshall said.
“We think the answers to those questions are clear: the Bureau has no authority to manipulate population data states use for redistricting, and the Bureau's decision to dramatically skew redistricting data is patently unnecessary and unlawful," Marshall said. “Those issues remain live in this case."
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