An earlier version of this column misspelled the name of Steven Romalewski. This version has been updated.

The presidency that celebrated “alternative facts” may be over. But those “alternative facts” may still poison the country for the next decade.

Unless, that is, the government acts swiftly to ensure that the recently completed decennial census is not tainted by the Trump era.

No census is easy, but the 2020 Census faced unusual challenges: Much of the population growth over the past decade has been among groups whom demographers consider “hard to count” (immigrants, people of color, others with low survey-response rates). Then came covid-19, which complicated in-person outreach and follow-ups. Knocking on doors or trying to extract information from nursing homes became especially difficult amid a pandemic.

Then, the Trump administration piled on.

Last year, Trump officials kept changing plans for census field work, ending such operations earlier than scheduled. Worse, President Donald Trump repeatedly attempted to politicize the census. He tried to jam through a new question on citizenship. He ordered granular counts of noncitizens and tried to exclude undocumented immigrants from the official population tallies.

Thanks to court challenges, an inspector general investigation and, ultimately, executive action from President Biden, Trump’s anti-immigrant orders have officially died. But his objectives may have been achieved anyway, by discouraging immigrants and minorities from participating in the census.

We don’t yet know how much Trump’s xenophobic policies might have chilled census response rates. Preliminary data shows that two-thirds of predominantly Hispanic or Black neighborhoods had lower self-response rates in 2020 than in 2010, according to an analysis of census tracts from Steven Romalewski of the Center for Urban Research at the City University of New York’s Graduate Center.

Other researchers have told me that some educational institutions withheld students’ names and other characteristics when contacted by the Census Bureau last year, because they worried the information would be used to track down immigrants.

All this made those “hard to count” populations even “harder to count,” as American Statistical Association President Robert L. Santos recently told me.

Making sure every single person gets counted is, to adapt a Bidenism, a big friggin’ deal. And not only because the Constitution explicitly requires it.

Census data determines how many congressional seats each state receives and how districts are drawn. It decides how billions of federal dollars are distributed. State and local officials rely on these numbers to design infrastructure, public services and crisis response plans.

The census is also the baseline against which virtually all other surveys — public or private — are calibrated.

If census data is flawed, it will distort virtually all other downstream measures. Which will, in turn, distort decisions made by the governments, businesses and families that rely on those measures — about where to locate, what to sell, whom to hire, what to study, how much to spend on a home and even whether politicians are delivering on their promises.

In other words, an accurate census is necessary for both our democracy and our economy to function.

The Census Bureau, for its part, has not been especially forthcoming about issues with the 2020 data, though it noted in court proceedings that it missed a statutory deadline for initial counts because of persistent data irregularities. (The agency did not reply to requests for comment.) In a Senate questionnaire, Commerce Secretary nominee Gina Raimondo did not mention the census as among the “top three challenges facing” Commerce (which oversees the Census Bureau), but she is likely to field questions on the subject during her confirmation hearing Tuesday.

Congress and Raimondo, if confirmed, must take steps right away so the 2020 Census results are both trustworthy and actually trusted.

First, Congress must give the Census Bureau more time to get its calculations right — moving back the statutory deadline so the agency can locate problems and fix them, including by cross-checking survey responses against more federal and state administrative records. The bureau also needs time to sort through some thorny privacy issues. These involve making sure that plans to disguise respondents’ personal details do not inadvertently make the data useless to local policymakers.

Additionally, Congress should appropriate more money for the annual American Community Survey. With additional funding, this in-depth survey could sample more people, giving states and cities better information about constituents.

The Census Bureau should also expand the appeals process for states and localities to challenge results of the decennial census, if they seem awry.

Finally, the Census Bureau owes lawmakers and the public greater transparency about how much political interference was attempted in recent years, what guardrails could prevent similar problems in the future and what issues remain with the 2020 data.

To many Americans, census results may seem like background noise, unimportant numbers to be taken for granted. But if the past few years have taught us anything, it is that without deliberately investing in a common, trusted source of facts, democracy may not survive.

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