After a controversial decision by the Department of Commerce to add a question about U.S. citizenship to the 2020 census, White House press secretary Sarah Huckabee Sanders defended the move as nothing out of the ordinary.

The claim

"This is a question that's been included in every census since 1965," Sanders said Tuesday, "with the exception of 2010, when it was removed."

The short answer

This statement is inaccurate, incomplete and misleading. A quick history of the decennial survey makes that clear.

The long answer

The census has been conducted every decade since 1790 to get a national head count used most critically to decide the distribution of congressional representation. At first it was conducted by U.S. marshals, but later surveys were sent to most American households, with census workers helping those who didn't promptly return their surveys.

The last time a census form sent to most American households asked a question about U.S. citizenship was in 1950. That form asked where each person was born and in a follow-up question asked, "If foreign born — Is he naturalized?"

In 1960 , there was no such question about citizenship, only about place of birth.

Sanders mentioned the year 1965 on Tuesday, but the census only comes every 10 years, so it isn't clear what she was referring to, and the White House did not respond to a request for clarification.

In 1970, the Census Bureau began sending around two questionnaires: a short-form questionnaire to gather basic population information and a long form that asked detailed questions about everything from household income to plumbing. The short form went to most households in America. The long form was sent to a much smaller sample of households, 1 in 6. Most people didn't get it.

Starting in 1970, questions about citizenship were included in the long-form questionnaire but not the short form. For instance, in 2000, those who received the long form were asked, "Is this person a CITIZEN of the United States?"

The short form kept it simple: name, relationship, age, sex, Hispanic origin, race, marital status and whether the home is owned or rented.

In 1996, the census added a new survey, the American Community Survey , conducted every year and sent to 3.5 million households. It asks many of the same questions as the census long-form surveys from 1970 to 2000, including the citizenship question .

Sanders said that in 2010 the citizenship question was removed. In fact, there was no long form that year — it had been replaced by the annual American Community Survey. The decennial census form asked just 10 questions.

The state of California has already sued to block the addition of a citizenship question to the 2020 census. The concern expressed by states with large undocumented immigrant populations is that asking about citizenship will scare people off, forms won't get filled out and the count won't be accurate, affecting federal funding and the number of congressional seats. (Though the Census Bureau is legally required to keep answers confidential , even from the FBI and other government entities.)

In a memo explaining his reasoning , Commerce Secretary Wilbur Ross dismissed concerns about incentive to participate.

"The Department of Commerce is not able to determine definitively how inclusion of a citizenship question on the decennial census will impact responsiveness. However, even if there is some impact on responses, the value of more complete and accurate data derived from surveying the entire population outweighs such concerns. Completing and returning decennial census questionnaires is required by Federal law, those responses are protected by law, and inclusion of a citizenship question on the 2020 decennial census will provide more complete information for those who respond," Ross wrote.

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