Will the census count all of America?

The US Constitution calls for an ‘‘actual Enumeration’’ of each state’s population every 10 years. This week, the Supreme Court will consider whether the Trump administration complied with that dictate when it sought to add to the 2020 census a question on whether the respondent is a US citizen. At the heart of the dispute lies the question: Who gets to be counted?

Federal law protects the privacy of everyone who responds to the census. But that’s small comfort for immigrants and their families living in a climate of fear under President Trump. Census Bureau officials have for decades recognised that communities with significant immigrant populations are likely to be undercounted if there is a citizenship question on the census.

Three federal judges have held trials and ruled that Wilbur Ross, the commerce secretary, who oversees the bureau, violated the law when he ignored available data and ordered the agency to move ahead with the citizenship question.

The agency has told Ross there are better alternatives to a citizenship question, such as deriving citizenship data from the American Community Survey, a longer questionnaire sent out annually that already asks such a question.

The census helps determine key aspects of representative democracy: how many seats in Congress will be apportioned among the states, and thus in the Electoral College; and the distribution of billions of dollars in federal funds.

Whether the nation gets an accurate and fair count of its residents is now in the justices’ hands.