The Supreme Court seemed wary Monday of approving President Donald Trump's plan to exclude undocumented immigrants from the census figures that are used to calculate each state's representation in Congress and share of billions of dollars from a host of federal programs.
But it was unclear after 90 minutes of oral argument exactly how the court would deal with the issue given that the Census Bureau concedes that it has no idea yet how many people would be excluded or when it will have the answer. The justices appeared to be reluctant to act immediately to block the plan.
"Career experts at the Census Bureau confirmed with me that they still don't know even roughly how many illegal aliens they will be able to identify, let alone how their number and geographic concentration may affect apportionment," said acting Solicitor General Jeffrey Wall, the government's chief lawyer.
Lawyers for the states that oppose the plan and groups affected by it told the justices that it would shift money and political power away from states with large immigrant populations and that it would violate the Constitution and federal law.
The Constitution requires a census every 10 years, and the results determine how many members of Congress each state gets in the House of Representatives. The data are also used to calculate local governments' share of $1.5 trillion under many federal programs.
Trump issued a memo in July that said people who are undocumented shouldn't be included in the final count. Under his plan, the Census Bureau would report two sets of figures to the White House — one including everyone who was counted and another allowing him to leave out undocumented immigrants. The president could then report the smaller number to Congress for use in reapportionment.
Trump's memo said states with policies "that encourage illegal aliens to enter this country and that hobble federal efforts to enforce the immigration laws passed by the Congress should not be rewarded with greater representation in the House of Representatives."
California, Florida and Texas would each lose one seat in the House, and Alabama, Minnesota and Ohio would each keep a seat they would otherwise lose to population shifts, according to an analysis by the Pew Research Center. Other predictions show Arizona losing a seat, too, and Montana gaining one.
The states would lose equal numbers of Electoral College votes, which are based on the size of their House delegations.
"The memorandum treats counting people as a reward to be withheld from states that house undocumented immigrants, even though our laws view counting people for apportionment as fact-finding, not giving or withholding a reward," New York's solicitor general, Barbara Underwood, told the court.
Wall said that federal law gives the president authority to direct how the census is conducted and that the term in the Constitution, which says the census must count "the whole number of persons in each state," has been generally understood to mean usual residents.
But several members of the court, including some conservative justices, seemed to doubt that the president had such sweeping power to modify the census results.
"If an undocumented person has been in the country for, say, 20 years, even if illegally, why would such a person not have a settled residence?" asked Amy Coney Barrett, the newest justice.
The court struggled, however, with what to do. Some justice suggested waiting until the Census Bureau transmits the figures to the White House or until the president gives Congress the population data to be used for figuring how many seats each state gets in the House.
Wall counseled waiting. "Based on my understanding from the Census Bureau, there is a real prospect that the numbers will not affect the apportionment," he said.
The court took the case on a fast track in order to issue a decision before the president is required to submit the census report to Congress in early January.