The Census Bureau warned last fall, that based on focus groups and pre-testing for the 2020 Census, its staff members were reporting increased fear among immigrants that the information they volunteered would be used against them and their families.
And on Tuesday, New York Attorney General Eric Schneiderman cited similar fears as he led 18 states, six major cities, and the U.S. Conference of Mayors in filing a lawsuit against the Trump administration for its inclusion of a citizenship question on the 2020 Census. The state of California has already filed a separate suit.
"This is a blatant effort to undermine the census," Schneiderman said at a news conference in New York. "Someone from the Trump administration knocking on your door asking about your citizenship status would provoke real fear." The states and cities contend they risk losing hundreds of billions of dollars in federal money if immigrant populations are undercounted.
The Census Bureau staffer reports include multiple examples - including participants providing incorrect information or leaving family members off the roster, attempts to break off interviews, and people who appeared "visibly nervous" - as evidence for their concerns that what they were seeing could foretell less participation in the 2020 Census and that "hard-to-count populations" would be missed.
These concerns flagged by Census Bureau staff preceded the December request by the Justice Department that a question on citizenship status be included on the 2020 Census form.
But even before the Commerce Department decided at the last-minute late last month to include the controversial question, Census Bureau staff cited concerns over current "political issues" and President Donald Trump wanting to end DACA - the Obama-era Deferred Action for Childhood Arrivals Program that protected undocumented immigrants brought to the U.S. illegally as children. The staffers said uncertainty over the program's future was feeding worries among immigrant populations about giving information to the government.
There are "potential barriers to respondent participation in the 2020 Census" that "are particularly troubling given that they impact hard-to-count populations disproportionately, and have implications for data quality," a September 20, 2017 memo for the Associate Directorate for Research and Methodology stated.
"The politics have changed everything," one field staffer was quoted as saying after conducting focus groups in the spring of 2017.
Both the memo and a November presentation by a Census Bureau staffer to the agency's National Advisory Committee on Racial, Ethnic and Other Populations noted a great reluctance among immigrants to be forthcoming, which the staff found concerning since some of the participants had been part of these type of focus groups and pre-testing measures in the past.
"Particularly with our current political climate, the Latino community will not sign up because they will think that Census will pass their information on and people can come looking for them," one interviewer observed.
The Commerce Department emphasized the privacy measures that surround census information.
There are "rigorous privacy standards of Census employees," a Commerce Department spokesperson told ABC News. "Census responses are safe, secure and protected by federal law. Answers can only be used to produce statistics. Every Census Bureau employee takes an oath to protect information received from respondents. Individual records are not shared with anyone, including federal agencies and law enforcement entities. Sharing personal data is punishable by hefty fines and up to five years in prison - or both."
Commerce Secretary Wilbur Ross' March 26 decision to include the citizenship question on the census has amplified concerns among Democrats, civil rights groups, government officials, and the academia that non-citizens would not participate, causing an undercount of the population that would particularly affect urban areas, which is where immigrants tend to live.
Census questions submitted to Congress
The 2020 Census questions were formally submitted to Congress last Thursday.
The citizenship question appears in the submitted document, which was obtained by ABC News, and is the second question on the census form (the first question asks a respondent's age).
"Is this person a citizen of the United States?" the question reads.
Under each question, the department provides a justification for its inclusion.
In their justification for this question, the department writes a "person's citizenship is used to create statistics about citizen and noncitizen populations" that are "essential for enforcing the Voting Rights Act and its protections against voting discrimination."
How and if the question will be amended or stricken is unclear. A lawmaker could propose legislation or an amendment to legislation to make a change but that proposal would have to make its through the normal legislative process, which means passing both chambers of Congress and being signed by the president.
Census staff requests additional support
The Census Bureau field staff, as a result of those focus groups and pre-testing results, requested additional support in the form of an advertising campaign "to overcome mistrust" and an "immigration statement to appear on the materials" when the 2020 Census begins.
Both participants in the focus groups and the staff who facilitated them suggested a message like, "Your information will not be shared with anyone, including other government agencies" be used.
However, the Census Bureau noted that it has "used similar statements in the past, but using such a statement now is problematic."
It's unclear if Ross or his staff was aware of the Census Bureau's memo or the November presentation to its census advisory committee. The Census Bureau referred ABC News to the Commerce Department, which did not address whether that information, which is publicly available on the Census Bureau's website, was seen.
However, a spokesperson for the department noted "Secretary Ross found that the need for accurate citizenship data and the limited burden that the reinstatement of the citizenship question would impose outweigh fears about a potentially lower response rate."
The spokesperson also noted there would be a "robust marketing and outreach effort" in "many different languages" for the 2020 Census. The department plans to spend $480 million on marketing and advertising, up from $376 million for the 2010 census.
It wasn't just census employees who noticed a greater reluctance among the immigrant community to participate in government programs.
Additional concerns about participation
Mesa, Arizona Mayor John Giles, a Republican, is concerned that non-citizens or even legal immigrants with non-legal family members will not want to participant in the census.
He cited the changes the Trump administration brought to DACA as a big cause of the mistrust among the immigrant community.
Arrests made in Washington and Mississippi shortly after Trump's election fueled concerns the new president would not continue the Obama administration's policy on the so-called Dreamers, the children of illegal immigrants.
"Why would we expect them to believe us?" Giles said to ABC News of the immigrant community. "It's going to be a very tough sell."
He fears this could be the "worst reported census in history."
Mayor Lydia Mihalik of Findlay, Ohio, has similar concerns about the response rate and noted the immigrant community is worried about "politicizing the question" on citizenship.
"We have enough trouble as it is getting people to respond to the census when it's done every 10 years and then we add things to it that could lead to a negative reaction that could impact our count," she told ABC News.
An undercount of the population could have a ripple effect that spreads to all parts of the country.
Census data impacts politically, socially, and economically
The Census touches every part of every person's life and in ways most don't think about. '
Census data is used to determine the distribution of the 435 House seats among the 50 states. Businesses use the data to make decisions like where to put a new store or what products to stock.
And $675 billion per year in the allocation of federal and state funding is dictated by the census, according to Census Bureau statistics.
That includes $311 billion in funding to Medical Assistance Programs, $71 billion for the Supplemental Nutrition Assistance Program, $38 billion for Highway Planning and Construction, $15 billion for Section 8 Housing Choice Voucher, $8 billion for Headstart and much, much more.
"If the census gets screwed up then everyone will feel it in multiple ways," Andrew Reamer, a research professor on census data at George Washington University, told ABC News.
Giles estimates in his city of Mesa, which has a population of 500,000 and is growing -- that for every 10,000 people undercounted, "more potholes will not be fixed and there will be fewer police."
"It's all about resources. The census is the gold standard used by every form of government - state, local, federal," he said.
Census staff warned of immigrant fears long before citizenship question