The U.S. Constitution empowers the Congress to carry out the census in "such manner as they shall by Law direct" (Article I, Section 2). In 1954, Congress codified earlier census statutes authorizing the decennial census as Title 13, U.S. Code.
This title does not specify census questions but it requires the Census Bureau to notify Congress of the actual questions to be asked two years before the decennial census.
In March 2018, Secretary of Commerce Wilbur Ross announced that a citizenship question would be added to the 2020 census in order to improve compliance with voting rights law. Governments in 18 states sued, alleging that the question would intimidate minorities and lead to a decline in the responses to census questionnaires.
On Friday, the Supreme Court ruled that the Constitution permits the secretary to inquire about citizenship, but that evidence did not support the secretary’s explanation for his decision. The court stated that government agencies should offer genuine justifications for important decisions.
The Supreme Court muddled some of the facts in its decision by ignoring the absence of citizenship questions in the first three censuses (1790-1810). It further biased the facts by mixing census questions on citizenship and on place of birth.
All but one census between 1820 and 2000 asked at least some of the population about their citizenship or place of birth, but only 13 of the 27 decennial surveys mentioned citizenship or naturalization. The last six censuses did not mention citizenship on short forms sent to the vast majority of households, instead confining the question to long forms sent to small random samples of the population.
In defense of Secretary Ross, former White House press secretary Sarah Huckabee Sanders said citizenship questions were normally included in every census from 1965 to 2000, but dropped in 2010. As is often the case with “facts” from the White House, however, history tells a different story:
* 1820-1830: First citizenship question asking if foreigners were naturalized.
* 1850-1890: Questions on place of birth; no citizenship question.
* 1900-1930: Questions on place of birth and naturalization.
* 1940: Question on citizenship.
* 1950: Naturalization question on both long and short census forms.
* 1960: Birthplace question on long forms, one-fourth of total. No citizenship question.
* 1970-1990: Birthplace and naturalization question on long forms, between one-fourth and one-sixth of total.
* 2000: Country of origin and citizenship on long forms, one-sixth of total forms.
* 2010: No birthplace and citizenship questions except on American Community Survey, which replaced long-form samples.
Critics of adding a citizenship question to the 2020 census have support from at least two sources of research.
The Urban Institute estimates an undercount that ranges from 0.27% to 1.22% of the total population. The Census Bureau estimates that over 5.1% of households would not respond to the questionnaires because of the citizenship question.
This would result in an undercount ranging from 139,000 to 561,000 persons even after the Census Bureau followed-up with non-respondents. The Census Bureau research estimates that adding the citizenship question would cost between $27.5 million and $91.2 million.