(CNN) In a controversial move, the Commerce Department announced Monday that the question of citizenship will again be included in the 2020 Census.

The move comes at the request of the Justice Department, first made in the early days of the administration, saying it was needed to better enforce the Voting Rights Act.

President Donald Trump's re-election campaign endorsed the idea in an email to supporters last week.

"The President wants the 2020 United States Census to ask people whether or not they are citizens. In another era, this would be COMMON SENSE... but 19 attorneys general said they will fight the President if he dares to ask people if they are citizens. The President wants to know if you're on his side," the email said.

Census data is used to determine where federal funds are spent and how congressional districts are drawn, among other uses. The Census is intended to count the entire population, not just US citizens.

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