A census worker studies forms for the 2010 count. (Gerald Martineau for The Washington Post)

CHICAGO — The Van Dorn, an overcrowded apartment building in the Rogers Park neighborhood, is Donald Trump’s worst nightmare, both as a luxury real estate developer and a nativist politician. Although its name connoted New York Knickerbocker elegance when it was built in 1923, the Van Dorn is now a shabby hive of tiny studios that overheat whenever the oven is dialed to 425. And a good number of the tenants in those studios are immigrants. As I found out when I worked as an enumerator for the U.S. Census Bureau in 2010, tracking down people who hadn’t sent back their forms, the Van Dorn is a port-of-entry building in a port-of-entry neighborhood.

In a single afternoon of knocking on the Van Dorn’s closely spaced doors, I met people from eight countries. There was an old Pole who lived in a one-room basement apartment, with a water pipe running below the ceiling. Although he spoke no English, he recognized the Census Bureau emblem on my black satchel. Inviting me inside, he set an Illinois state ID next to his dinner plate, so I could write down his name and age.

“He don’t know English,” said the building manager, who was from Mexico, “but he’s a really good plumber.”

On the first floor, I met a South African, a Native American and a woman from Colombia. The Census Bureau asked for ethnicity, and most people identified themselves by their home countries. On the third floor, I met a Mongolian.

As ProPublica recently reported, the Justice Department is asking the Census Bureau for the 2020 count to add a new question about citizenship. The department’s reasoning: To enforce the Voting Rights Act, it “needs a reliable calculation of the citizen voting-age population in localities where voting rights violations are alleged or suspected.” That’s not the first time the Trump administration has suggested adding a citizenship question. In February, The Washington Post reported on a draft executive order proposing “questions to determine U.S. citizenship and immigration status on the long-form questionnaire in the decennial census.”

As someone who worked as an enumerator in one of the most immigrant-heavy neighborhoods in the United States, I can tell you that asking respondents about their citizenship will make the next census both less accurate and more expensive. It would have made my work more difficult and time-consuming. Enumerators will have to ask about citizenship, as well as hunt down and gain the cooperation of people who didn’t return forms in part specifically because they didn’t want to answer that question.

For an enumerator, gaining the trust of the people behind the doors — many of them strangers in this country, at least in census tracts like the ones where I worked — is what makes the rest of the job possible. During training, my supervisor made it clear that none of the information we collected would be reported to law enforcement, an assurance I passed on to several nervous interviewees. Our job was to count everyone in the country, no matter why they were here. The fact that the Census Bureau is an arm of the federal government already depresses numbers in immigrant neighborhoods. (One estimate from 2010 suggested that young Latinos were undercounted by 7.1 percent, compared with 4.3 percent for young non-Latinos.) Although all Chicago wards are supposed to contain the same number of residents, one alderman who represents a Mexican American neighborhood is convinced that his is the most populous because it generates the most garbage. If the Census Bureau starts sniffing around for citizenship status, those numbers could be drop even more — especially because the question will be coming from a government run by a president who ran on an anti-immigrant, nativist platform. (According to the American Community Survey, which the Census Bureau uses to estimate citizenship rates, a third of Rogers Park residents are noncitizens. Nationwide, the figure is 7 percent. So our neighborhood would be at a huge disadvantage if immigrants are discouraged from responding to the 2020 census.)

Steve Jost, the Census Bureau’s chief strategist for data dissemination in 2010, told Pro Publica that he believes a citizenship question will discourage participation. “People are not going to come out to be counted because they’re going to be fearful the information would be used for negative purposes,” Jost said. “This line about enforcing voting rights is a new and scary twist.”

In a Sept. 17 memo, Census Bureau staffers reported a rise “in respondents spontaneously expressing concerns about confidentiality in some of our pretesting studies” since Trump took office, the New York Times reported. “[R]esearchers heard respondents express new concerns about topics like the ‘Muslim ban,’ discomfort ‘registering’ other household members by reporting their demographic characteristics, the dissolution of the ‘DACA’ (Deferred Action for Childhood Arrival) program, repeated references to Immigration and Customs Enforcement (ICE), etc.

“Respondents reported being told by community leaders not to open the door without a warrant signed by a judge. … Researchers observed respondents falsifying names, dates of birth, and other information on household rosters.”

Maybe lower participation among immigrants is just what the Trump administration wants. The 14th Amendment prohibits the Census Bureau from limiting the count to citizens only, dictating that “[r]epresentatives shall be apportioned among the several States according to their respective numbers, counting the whole number of persons in each State.” That clause was added to win the support of states with large immigrant populations. Those states would suffer — in representation and allocation of federal resources — if immigrants skip the Census. That would be no skin off Trump’s nose: Eight of the 10 states with the largest percentage of immigrants voted for Hillary Clinton in 2016.

Whatever the next census form looks like, I hope the residents of the Van Dorn fill it out and send it back. If they don’t, I’m not going to knock on their doors again. Working as a census enumerator was the fulfillment of a longtime ambition: I got a badge that allowed me to peek inside strangers’ apartments, and the information I collected became part of American history. I enjoyed the job so much that I signed up to conduct the American Housing Survey in 2015. But I won’t work on the 2020 Census, because I’ve never believed the Trump administration wants to count everyone living in this country, and I’m not going to go out and catch the flak for mistrust of the president’s motives. Proposing a citizenship question is evidence of that, and I’m not going to participate in a process designed to disadvantage my own neighborhood and immigrant neighborhoods all over this country.

CORRECTION: An earlier version of this story misstated the request the Justice Department was making. The citizenship question would be on the basic census form that goes to all households. The long form is no longer in use.

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