The Trump Administration has announced that it will ask a citizenship question on the 2020 census, and California Attorney General Xavier Becerra has already filed a lawsuit to stop it. The only problem is, the citizenship question is already being asked, and has been for two decades.

A little history. From 1820 until 1950 the census asked whether you were an immigrant, a naturalized citizen or native born. For many decades it even asked where your parents were born. This was the result of a desire to get a complete picture of the country, especially during the many decades of high immigration.

In 1960, the citizenship question was dropped because of the very low number of non citizens. The great European migration to America ended with the coming of the Great Depression in 1929; by 1960 only a small number of elderly people were not American citizens.

But by the 1990s, America was again experiencing a large influx of immigrants, and no longer mostly from Europe. In 2000, the Clinton Administration added the citizenship question back into the census, but only on the “long form,” a special form sent to about five percent of respondents.

In 2005, the long form was replaced by an on-going annual questionnaire called the American Community Survey. Here is the citizenship question as it is asked today, taken from the ACS questionnaire.

This is the reason the Census Bureau gives for asking this question: “We ask about people in the community born in other countries in combination with information about housing, language spoken at home, employment, and education, to help government and communities enforce laws, regulations, and policies against discrimination based on national origin. For example, these data are used to support the enforcement responsibilities under the Voting Rights Act to investigate differences in voter participation rates and to enforce other laws and policies regarding bilingual requirements.”

All the Trump Administration is doing is expanding this question from the ACS to the entire census, so everyone will be asked to answer the question, as was the case up to 1950. The question does not ask whether a person is legally in the United States, nor has it ever.

Becerra and the state’s Democratic establishment are attacking the question because they assume it will keep illegal immigrants from filling out the census forms, thus California’s population will be undercounted and the state will lose federal benefits. This could be true, but will be very hard to prove.

A 2014 government funded study during the Obama Administration found that asking about citizenship did not stop immigrants from filling out a census survey, and that even applied to the questions of legality. “The introduction of legal status questions does not appear to have an appreciable ‘chilling effect’ on the subsequent survey participation of unauthorized immigrant respondents.”

There is no sign that the ACS citizenship question has led to reduced participation. For one thing, legal immigrants should have no concerns about answering this question. Most immigrants are here legally, whether with visas, green cards, spousal rights or other forms of legalization. Undocumented immigrant households may include American born children, who are automatically citizens. Additionally, if respondents say they are legal but are not, there is little the government can do about it.

But there will be a census undercount, there was in 2010. The Census Bureau estimates that 1.5 percent of Latinos were not counted, and 2.1 percent of blacks. The undercounted people live in poor areas, are hard to reach, and may not want to be counted.

The Trump Administration’s rhetoric about enforcing immigration laws may well be forcing undocumented people farther into the shadows, thus they will be harder to find and count whether the citizenship question appears on the form or not. And obviously, some people simply will not answer this question.

This is not an issue of constitutional law, there is really no constitutional argument that a question asked for a century and half, and regularly this decade by the ACS, is somehow unconstitutional. This is about politics.

In February 2017, Pew Research estimated that there are about 11 million undocumented immigrants in this country and they overwhelmingly live in large cities. Pew finds that they are concentrated in the following states: New York, New Jersey, Pennsylvania, Illinois, Florida, Georgia, Texas, and of course California. And they are found in the Democratic voting parts of these states.

If they are not counted, Democrats will lose representation in Congress and the legislatures. Thus it will be imperative upon the Democrats to make sure all immigrants are counted. This may well be more difficult than it was a decade ago because of the focus on illegal immigrants and calls to deport them. This rather than the citizenship question is the most likely factor in the hesitation of people here illegally to participate in the 2020 Census.

Democrats should admit that fact, and they should begin a well-funded outreach effort to make sure an undercount does not occur.