Trump is trying to add a question to the 2020 Census about citizenship status, likely for a court challenge to reduce Congressional representation for blue states by depressing immigrant responses.
Thankfully, this process is rather involved.
Gerard Magliocca looks at the question, and comes up with a brilliant question to add to the census:
I have a separate suggestion. If we are going to add new questions to the census about citizenship, then I would propose reviving one that was asked in the 1870 census. The modern version would ask all citizens above the age of 18 whether their right to vote has ever been “denied . . . or in any way abridged, except for participation in rebellion or other crime.” This is language from of Section Two of the Fourteenth Amendment, which states that if states deny or abridge suffrage to presumptively eligible voters to excess then their representation in Congress shall be reduced.
It’s never gonna happen, but that made my day.