No, the census has never been delayed. Even when it was really hard to conduct.

President Trump tweeted Thursday that he had asked “the lawyers” if the 2020 Census could be delayed, “no matter how long,” following the Supreme Court’s decision to put on hold the inclusion of a citizenship question.

So, in 220-plus years, has there ever been a delay to the census?

“No,” historian Margo J. Anderson, author of “The American Census: A Social History,” said in a phone interview with The Washington Post. “And the date is set in statute.”

The exact date of the census is determined by Congress. Census Day has varied over time, but since the 1930 count, the official date has been April 1. And while the process has at times been complicated by a tug-of-war between the executive and legislative branches, the count has never been delayed. Not in the lead-up to the Civil War, not during the Great Depression, not for any reason at all.

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The government has never asked a citizenship question of everyone in the country, the academics said. Though past censuses did ask for citizenship questions of some respondents until 1950, developments in statistical methodologies revealed the extent to which such questions led to undercounting.

“The Census Bureau has worked very hard over 200 years to learn how to do accurate, scientific survey research,” Anderson said. “The addition of this question didn’t draw upon that expertise.”