The Supreme Court ruled that there was insufficient justification provided for adding the question.

I am trying to look at this objectively. Wouldn’t it be helpful to have information about the current number of potential voters? Opponents say that some non-citizens may not be willing to fill out the census form if contains a citizenship question. Why is that? Do they think that they will be deported? Would they in fact risk deportation? What if people filled out the rest of the form but refused to answer that one question?