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How The Citizenship Question Could Break The Census

This is the Trump Docket, where we track some of the most important legal cases of the Trump presidency and how their results could shape presidential power. Questions, comments or thoughts about cases to cover? Email us here.

Every 10 years, the Constitution requires the government to count all the millions of people living in the United States. The decennial census is a massive, painstaking undertaking that results in a national portrait in numbers. It tells us how many people live here, where people have moved and how our country’s racial and ethnic makeup has changed. And today the Supreme Court will weigh whether asking respondents whether they are U.S. citizens would undermine the census’s mandate to count every person.

A lot is determined by the data from each census, which is why adding or subtracting survey questions can be contentious. In addition to determining how many seats in the U.S. House each state has, census data touches almost every corner of American life, including business, education and polling, to name a few. “These numbers are the gold standard body of statistics that make the country run,” said Thomas Wolf, counsel for the Democracy Program at the Brennan Center for Justice. Critics of the proposal to add a citizenship question to the census are concerned that if a large number of immigrants don’t respond or respond incorrectly, the results will be inaccurate, and as a result, certain areas of the country will lose funding or political representation. Both parties could be affected, since an undercount of immigrants would likely hurt red states like Texas and blue states like California.

Questions related to a person’s citizenship did once appear on the census, but historians say the phrasing and intent of those earlier questions were different — and, in any case, they were removed from the main head count after 1950 in a bid to improve the census’s accuracy. Meanwhile, social science methods have evolved to the point that high-quality citizenship data can be — and already is — collected via other Census Bureau surveys and administrative records. So the Trump administration is facing an important question: Why add a question to the census that could harm the quality and credibility of the data — and also may not be necessary?

The case before the Supreme Court is about the legality of Commerce Secretary Wilbur Ross’s decision to add a citizenship question to the 2020 census; it has been challenged by an array of states and civil rights organizations. Ross says the question was added in response to a request from the Justice Department for more detailed citizenship data to help enforce the Voting Rights Act, but three lower court judges have all concluded that the evidence shows he had already decided to add the question and used the Justice Department as a pretext. The judges concluded, too, that the administration violated standards of transparency and accountability required of executive agencies by failing to test the question and ignoring expert advice against adding it. Two also ruled that the question would violate the Constitution because it seems likely to result in an undercount.

But the Trump administration maintains that the question isn’t even all that revolutionary. In the government’s telling, the citizenship question is being “reinstated” — a claim that was echoed by Justice Neil Gorsuch in a dissent last fall on the Supreme Court order that allowed a trial in one of the citizenship question cases. “Most censuses in our history have asked about citizenship,” Gorsuch wrote. This argument certainly makes Ross’s decision look more reasonable, both from a procedural perspective and a constitutional perspective. But historians say it overstates the extent to which citizenship-related questions have been a fixture on past censuses.

Margo Anderson, who is a retired professor at the University of Wisconsin-Milwaukee and studies the demographic history of the U.S., signed onto an amicus brief outlining the history of the census in support of the administration’s challengers. She told me that even though questions about immigration status have previously appeared on the census, a question directly asking every household whether every resident is a citizen has not.1 When questions about citizenship status were included in the past, Anderson said, they were sporadic and asked only of certain groups and were sometimes accompanied by additional questions about whether people were trying to become citizens. The 1890 census, for instance, specified that only “males of foreign birth” who are 21 years or older be asked whether they were naturalized and whether they had “taken out papers” to become naturalized. In 1950, the census asked whether people who were “foreign born” were “naturalized.”

Often the purpose was to determine how immigrants were being assimilated and whether they had started the naturalization process. The difference now, Anderson said, is that “the question that’s being proposed by the Trump administration has an exclusionary function — are you a citizen, yes or no.”

Wolf, who co-authored a recent paper about the history of citizenship questions on the census, said that in the mid-20th century, large numbers of demographic questions, including one related to citizenship, were removed from the full survey received by everyone and added to a longer supplement that only went to a subset of households, because new statistical methods showed researchers that a single, more cumbersome survey was causing an undercount. Anderson echoed Wolf’s findings and said that although it’s hard to say for sure because the question hasn’t been tested, there’s evidence that the addition could cause respondents to skip the citizenship question, decline to fill out the form or leave relatives off the form, or inaccurately claim citizenship. Statisticians and social science researchers have expressed concerns that immigrants and their families, in particular, may be less likely to respond to the census or may respond inaccurately out of fear that the data could be used for immigration enforcement.2

One of the main criticisms of the Trump administration by the states and organizations challenging the question is that it hasn’t made the case for why citizenship data needs to be gathered on the census and doesn’t seem sufficiently concerned about how the addition of the question will affect the accuracy of the count. Kenneth Prewitt, a professor at Columbia University and a former Census Bureau director, told me that high-quality citizenship data is available from other census surveys and administrative records. Indeed, there already is a citizenship question on a separate, longer Census Bureau survey that is sent to a small share of households on a monthly basis. “Adding this question to the decennial census is not necessary,” Prewitt said.

And Justin Levitt, who is a law professor at Loyola Law School Los Angeles and worked in the Justice Department’s civil rights division in the Obama administration, said there are few situations where the census’s highly granular data is necessary to determine whether a minority group is protected under the Voting Rights Act. Instead, Levitt said, the reverse could be true: Inflated or otherwise inaccurate citizenship numbers in a particular area could result in a minority group not getting protections.

Regardless of how the case turns out, some damage to the census’s credibility as a nonpartisan, scientific tally may already have been done. “It’s like an election — we have to agree that the results are fair,” Anderson said. And by drawing the census into the broader debate about immigration, the Trump administration may have already helped stoke mistrust in the final result — even if the citizenship question never ends up on a census form.

Other cases

President Trump

Trump and his businesses filed a lawsuit against House Oversight and Reform Committee Chairman Elijah Cummings, in response to a congressional subpoena for Trump’s personal financial information. The lawsuit argues that the subpoena is invalid and unenforceable because it has no “legitimate legislative purpose.”

The Trump administration

  • The 9th U.S. Circuit Court of Appeals ruled against the Trump administration in a case involving California’s sanctuary law. The decision said that the law, which limits cooperation between state law enforcement and federal immigration authorities, doesn’t improperly interfere with the federal government’s ability to enforce immigration laws in the state. The court did rule in favor of the Trump administration on another point, however, blocking part of another California law that would have required state inspection of how detainees were apprehended and transferred to federal immigration detention facilities and asking the lower court judge to reconsider the economic burden on the federal government.
  • The U.S. House of Representatives filed a lawsuit that targets members of the Trump administration over Trump’s use of an emergency declaration to fund a wall on the U.S.-Mexico border. The lawsuit argues that this move violated the Constitution’s appropriations clause, which gives Congress control over how federal money is spent.
  • A federal judge in New York ruled that the Trump administration can’t revoke temporary protected status for Haitians, at least for now. In his opinion, the judge said that the decision to take away the special immigration classification, which was granted after a 2010 earthquake in Haiti, was motivated by improper political considerations.
  • The 9th U.S. Circuit Court of Appeals temporarily lifted a lower court’s injunction against a policy that requires migrants who are seeking asylum to wait in Mexico while their cases move forward.

From ABC News:

Commerce Secretary defends effort to add citizenship question to 2020 census


  1. The proposed 2020 question is: “Is this person a citizen of the United States?”

  2. Census Bureau officials have pointed out that census data is, by law, confidential and can be used only for statistical purposes. However, it has been used against specific populations in the past: During World War II, census data was used to target Japanese Americans for internment.

Amelia Thomson-DeVeaux is a senior editor and senior reporter for FiveThirtyEight.