The Supreme Court's conservative justices seemed ready Tuesday to preserve the Trump administration's addition of a question about a person's citizenship status to the 2020 decennial census.

The case, Department of Commerce v. New York, is the high court's first direct look at an administration policy since it upheld the "travel ban" last year, SCOTUSBlog reports. It concerns the administration's attempt to add a question asking respondents "is this person a citizen of the United States?" to the 2020 census.

That question has appeared on the long-form Census for decades, as well as on the American Community Survey and Current Population Survey, two large-scale annual surveys conducted by the Census Bureau to estimate key statistics about the population.

But this fact did not deter objectors from the left, who argued that it would reduce response rates among illegally resident people. This, they argued, would lead to inaccurate estimates of figures used to calculate federal aid and congressional apportionment, among other things.

This concern was strong enough that a group of 17 states, lead by New York, sued the Department of Commerce to get an injunction on the question. They argued that the decision to add the question was "arbitrary and capricious and contrary to law," in violation of the Administrative Procedure Act. A lower court agreed, enjoining the addition of the question, at which point the administration appealed to the Supreme Court.

At oral arguments on Tuesday, however, it seemed like the balance of the court was swinging against New York. Justices John Roberts and Brett Kavanaugh directed most of their questions towards the state's lawyer, with Kavanaugh arguing that Congress gave the Secretary of Commerce "huge discretion" to select questions.

Justices Neil Gorsuch and Samuel Alito, for their part, pushed back on the idea that a citizenship question would reduce response rates in-and-of itself, suggesting that other factors which differentiate citizens and non-citizens may explain any disparities. The liberal justices, for their part, seemed intent on agreeing with the claim that a question about citizenship would undermine the accuracy of the census's count.

"There's no doubt that people will respond less," Justice Sonia Sotomayor said.

A decision in the case is expected over the summer. The Census will be carried out beginning April 1, 2020.