Rep. Don McEachin, D-4th, is asking the Census Bureau to reconsider its plans for analyzing data from the 2020 population count, echoing concerns from researchers at the University of Virginia that argue the agency’s mathematical procedure will distort the data.
The letter raises questions about the bureau’s plans to use a technique called “differential privacy” when reporting census results that will inject the data with “noise” to minimize the chances an individual will be personally identifiable.
The letter — signed by 33 members of Congress, all Democrats — argues the procedure could distort data at the regional, district and town level, risking public funding for some communities and potentially distorting the new political maps.
The population count, which the U.S. Constitution calls for every 10 years, is ongoing in Virginia and elsewhere, and residents have until Sept. 30 — next Wednesday — to complete their form. Results from the census are used to allocate public funding, right-size public services and reapportion seats in the legislature and House of Representatives.
For small localities with distorted data, “the differences can be radical and debilitating,” McEachin said.
Researchers at UVA’s Weldon Cooper Center for Public Service have raised concerns about the new procedure since the start of the year. According to its analysis, the proposed procedure may lead to a population shift from urban to rural areas, and from large race groups to small race groups.
“A rural, declining, old, predominant white community, for example, may appear instead growing, younger, and more diverse,” the center wrote in a letter to Gov. Ralph Northam in January.
For example, the center applied the proposed algorithm to 2010 data and found that if it had been used at the time, the population of Port Royal in Caroline County would have been artificially increased by 87 percent, while the population of Stony Creek in Sussex would have declined by 43 percent.
Demographers at other institutions have echoed similar concerns.
In an Associated Press article from December, Ron Jarmin, deputy director of the Census Bureau, said the agency is at an “important crossroads,” and searching for the “sweet spot” between privacy and accuracy.
McEachin said the highly technical changes may amount to political gamesmanship on the part of the administration.
“We’ve been aware that the Trump administration is trying to play games with the census since he came into office,” McEachin said, referring to the administration’s efforts to include a question about citizenship status in the survey.
“Sometimes we find that when we expose them, they back down.”
McEachin and his colleagues, including Rep. Gerry Connolly, D-11th, are asking the Census Bureau to provide Congress with more information about how it is evaluating and testing the new mathematical procedure, and how it is incorporating feedback from experts and the public.
“It is essential that sub-state level census data be accurate and reliable,” it reads.
As of Tuesday evening, the Census Bureau had not responded to McEachin’s letter, according to the congressman’s office.