An internal Census Bureau document sent to members of Congress and obtained by NBC News warned that the new truncated deadline set by the agency's director last month has the potential to undermine the integrity of the count and lead to "serious errors."
The document was sent to the House Oversight Committee, which has been investigating the Census Bureau for several years since its failed attempt to add a citizenship question to the decennial count.
The document appears to be a presentation for Commerce Secretary Wilbur Ross, who oversees the agency, dated Aug. 3, 2020, and marked "Not for Public Distribution." No author is listed on the document, and it is not clear what section of the bureau it came from. Oversight Committee Chairwoman Carolyn Maloney, D-N.Y., wrote in a letter to congressional leaders Wednesday that she obtained the document from a "source," rather than from one of the agency's leaders.
Census Director Steven Dillingham said last month that the agency would end all of its counting efforts on Sept. 30, a month sooner than previously expected. In-person operations will end even sooner in some areas, including San Diego. The internal document warns that the "highly compressed" timeline, as well as limits on activities like door-knocking and data review, will lead to less accurate results.
"A compressed review period creates risk for serious errors not being discovered in the data — thereby significantly decreasing data quality," the document says. It adds, "Additionally, serious errors discovered in the data may not be fixed — due to lack of time to research and understand the root cause or to re-run and re-review one or multiple state files."
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The agency will also have far less time and fewer resources to review the data than in previous years, the document says. This year, the document says, the bureau will process data in only 92 days. The 1990 Census took 140 days, the 2000 Census took 185 days, and the 2010 Census took 147 days.
The document is the latest indication of the issues plaguing the Census Bureau as it fulfills its constitutional mandate to count all persons living in the U.S., which determines congressional seats and affects federal aid sent to states, among many other areas. About 65 percent of households have so far self-responded to the census, according to the agency, with 19 percent more counted by in-person efforts.
The move has raised fears among civil rights groups, researchers and other experts who say significant parts of the population, such as minorities and immigrants, could be left of out the tally.
"This is really an insidious ploy to have cities that have large immigrant communities, in particular, to lose congressional representation and to have that representation moved to red Republican areas," New York City Census Director Julie Menin said last month. "That's what this whole battle is about."
The agency requested bipartisan action in the spring to extend its mandated Dec. 31 deadline to turn in data to federal and state governments until April 30.
In her letter Wednesday, Maloney urged Democratic and Republican leaders in the House and the Senate to extend the deadline to ensure that the census is accurate. House Democrats passed a bill in May to push the deadline because of the coronavirus pandemic, but legislation is stalled in the Republican-controlled Senate.
"In light of this new internal document and the additional information we have obtained, it is more urgent than ever that the Senate act," Maloney said in the letter Wednesday. "Congress has a solemn responsibility under the Constitution to help ensure an accurate and complete count, and there is bipartisan support in the Senate for extending these deadlines."