The Supreme Court said Friday that it was premature to decide whether President Trump has the authority to exclude undocumented immigrants when determining the size of each state’s congressional delegation, dismissing a case that challenged his intentions.

The court’s unsigned opinion in Trump v. New York said the constitutional and legal questions surrounding such action should wait until it is known if Trump will be able to act on his plan. The government has said the Census Bureau might not be able to come up with the population figures Trump seeks before he leaves office.

Trump is trying to change two centuries of reapportionment practice, and the court’s decision at least theoretically gives him a chance to act before President-elect Joe Biden takes office next month.

But the court’s conservatives said there is too much unknown at this point to get involved and said a decision would violate its norms on when justices have the authority to act.

“At present, this case is riddled with contingencies and speculation that impede judicial review,” said the opinion. It acknowledged that Trump has “made clear his desire to exclude aliens without lawful status” but only “to the extent feasible.”

“Any prediction how the executive branch might eventually implement this general statement of policy is no more than conjecture at this time,” the opinion said.

The court’s three liberal justices disagreed and said it already is evident Trump lacks the power to claims to subtract the undocumented from total census numbers.

History, practice and the text of federal law make clear that Congress chose “a view of democracy wherein the representatives are apportioned based on ‘the whole number of persons in each state,’ not the whole number of voters, citizens, or lawful residents,” Justice Stephen G. Breyer wrote in a dissent joined by Justices Sonia Sotomayor and Elena Kagan.

He added: “The government acknowledges it is working to achieve an allegedly illegal goal, [and] this court should not decline to resolve the case simply because the government speculates that it might not fully succeed.”

Dale E. Ho, director of the American Civil Liberties Union Voting Rights Project, noted that the majority opinion did not address the arguments against Trump’s action.

“This Supreme Court decision is only about timing, not the merits,” he said in a statement. “If this policy is ever actually implemented, we’ll be right back in court challenging it.”

Paul Smith, vice president at Campaign Legal Center, said the court “seems content to run out the clock on the Trump administration, anticipating that it will fail to put into action a plan to exclude undocumented immigrants from the census before January 20.”

But Terri Ann Lowenthal, a former staff director of the House census oversight subcommittee, said the delay could cause problems.

“The ruling leaves the final census number-crunching and apportionment process shrouded in greater uncertainty,” she said. “The president could be more emboldened to rush data processing against the expert judgment of Census Bureau staff.”

For the first time in the nation’s history, Trump this summer claimed the authority to exclude undocumented residents when reapportioning Congress.

In a July memorandum, Trump indicated that he believed some states would be getting greater representation than deserved — California was implied but not named — because of their numbers of undocumented residents.

He directed Commerce Secretary Wilbur Ross to provide him with two sets of numbers, one that includes unauthorized immigrants and one that does not, “to the maximum extent feasible and consistent with the discretion delegated to the executive branch.”

Opponents of his plan said it is foreclosed by more than 200 years of practice, the text of the Constitution and the authority granted the president by Congress. Three lower courts have ruled against Trump, and a fourth said the time was not ripe for a decision on the question’s merits.

Legally, the challengers said, Trump’s intentions are directly contradicted by the Constitution’s requirement to base apportionment of the House of Representatives on “the whole number of persons in each state” as determined by the once-a-decade census.

But the president’s lawyers told the Supreme Court when the case was argued last month that it is up to the president to decide whether undocumented immigrants should be counted, a decision that could have far-reaching implications for a state’s representation in Congress and power in the electoral college, and for billions of dollars in federal funds.

At the same time, acting solicitor general Jeffrey B. Wall told the court that it was unclear whether the Census Bureau could produce reliable numbers before the end of the year, when the report is due.

The Supreme Court last year said the administration could not ask a citizenship question on the census form because it had not done the necessary work to show it would not harm the count’s accuracy.

Neither the Census Bureau nor the Commerce Department responded to questions about when it would produce state population totals and figures accounting for undocumented immigrants.

To the surprise of other Census Bureau staffers, a high-level career official there said recently that it would finish tallying undocumented immigrants by state by the first week in January, according to a person familiar with ongoing work at the bureau who spoke on the condition of anonymity due to the subject’s sensitivity.

However, state population totals may not be ready by then. Additionally, in the past couple of weeks, the bureau has discovered a data problem considered serious enough that officials temporarily halted further processing, the person said.

Previously detected anomalies affecting more than a million records were expected to delay delivery of apportionment numbers until after Trump leaves office Jan. 20, lawmakers disclosed this month, citing internal documents they obtained.

In a recent report, the Government Accountability Office said the bureau had not provided information it had requested about changed time frames for response-processing and its plans for ensuring accuracy in the data it delivers.

The report said that because the bureau compressed its response-processing time from 153 days to 77, it “faces increased risk that system defects or other information technology issues may go undetected, affecting the quality and accuracy of the count. Additionally, the Bureau will have less time to address issues that arise.”

No one disputes that eliminating the undocumented would shift representation from some more diverse states with large immigrant populations,

A Pew Research Center study this summer found that if the country’s undocumented immigrants were excluded from apportionment, California, Texas and Florida would end up with one less seat, while Minnesota, Ohio and Alabama would end up with one more, compared with what they would have gotten with no adjustments.

The court’s majority opinion noted that any report from Ross and the Census Bureau has to be specific: “Everyone agrees by now that the government cannot feasibly implement the memorandum by excluding the estimated 10.5 million aliens without lawful status,” it said.

But the liberal justices said the administration was purposefully lowballing its ability to identify those it wants to exclude.

“All told, the bureau already possesses the administrative records necessary to exclude at least four to five million aliens,” Breyer wrote. “Those figures are certainly large enough to affect apportionment.”

The census report is supposed to be submitted to the president by the end of the year. It is up to the president then to inform Congress within one week of the opening of its next session how its 435 seats are to be allocated. The House clerk then has 15 days to inform the states of the number of representatives to which each is entitled.

If the bureau cannot present accurate numbers to Trump, the reapportionment task would fall to Biden after he takes office as president.