The US Justice Department says it will push for the inclusion of a citizenship question on the 2020 Census.
The US Justice Department says it will press its search for legal grounds to force the inclusion of a citizenship question on the 2020 Census, hours after President Donald Trump said he is "very seriously" considering an executive order to get the question on the form.
Trump said Friday his administration is exploring a number of legal options, but the Justice Department did not say exactly what options remain now that the Supreme Court has barred the question at least temporarily.
The government has already begun the process of printing the census questionnaire without that question.
The administration's focus on asking broadly about citizenship for the first time since 1950 reflects the enormous political stakes and potential costs in the once-a-decade population count that determines the allocation of seats in the House of Representatives for the next 10 years and the distribution of some $US675 billion ($A966 billion) in federal spending. It also reflects Trump's interest in reshaping how congressional districts are drawn.
"You need it for Congress, for districting," he said Friday. "How many people are there? Are they citizens? Are they not citizens? You need it for many reasons."
Districts now are based on the total population. Some Republicans want them based on the population of eligible voters, a change that could disadvantage Democrats by excluding immigrants. The Supreme Court has left open the issue of whether districts based only on the population of eligible voters is constitutional.
The Census Bureau's own experts have said a citizenship question would discourage immigrants from participating in the survey and result in a less accurate census that would redistribute money and political power away from Democratic-led cities where immigrants tend to cluster to whiter, rural areas where Republicans do well.
Trump, speaking as he departed the White House for a weekend in New Jersey, said he might take executive action.
"It's one of the ways that we're thinking about doing it, very seriously," he said.
An executive order would not, by itself, override court rulings blocking the inclusion of the citizenship question. But such an action from Trump would perhaps give administration lawyers a new basis to try to convince federal courts that the question could be included.