Washington (CNN) As the Trump administration defended its move to add a citizenship question to the 2020 census at the Supreme Court Tuesday, the nation's first Latina justice leveled an impassioned, persistent counterattack from the bench.

Justice Sonia Sotomayor interrupted US Solicitor General Noel Francisco before he could complete his second sentence and did not let up on the government's top lawyer through the end of his allotted time at the lectern.

Like her colleagues on the left, Sotomayor sharply challenged the Trump administration's proposal adding the citizenship query to the decennial effort intended to count everyone irrespective of legal status. But Sotomayor's questions were far more numerous and heated.

She also emphasized the fears among Hispanics about responding to a citizenship query.

"There is no doubt that people will respond less," she insisted. "That has been proven in study after study. One census surveyor described an incident where he walked into a home, started asking citizenship, and the person stopped and left his home, leaving the census surveyor sitting there."

Sotomayor's approach recalled other instances over the past decade that the Obama nominee, born of Puerto Rican parents in the Bronx, has given voice to her distinct background on the majority-white bench.

It also offered a reminder of how deeply America's highest court is divided on dilemmas involving race and ethnicity. Tuesday's arguments overall suggested the five-justice conservative majority would uphold the Trump administration decision to add the citizenship question, over the dissent of the four liberals, including Sotomayor.

Census Bureau officials have predicted a citizenship question would lead to an undercount of Hispanic and noncitizen households, which New York and other state challengers say would translate into less federal funding and political power for mainly Democratic locales. The decennial population count is used to apportion members of the US House of Representatives, draw state political districts and allocate hundreds of billions of dollars in government funding.

When Commerce Secretary Wilbur Ross ordered the citizenship question added last year, he said the Justice Department believed that resulting data would lead to better enforcement of voting rights.

Lower court judges rejected those grounds as a pretext and declared the secretary's action -- taken without the usual Census Bureau testing and safeguards for new questions -- violated federal procedural rules and the Constitution's enumeration clause.

As Francisco appealed to the justices to overturn the lower court finding, he insisted, "There's no evidence in this record that the secretary would have asked this question had the Department of Justice not requested it. And there's no evidence in this record that the Secretary didn't believe that the Department of Justice actually wanted this information to improve Voting Rights Act enforcement."

Chief Justice John Roberts suggested he found that assertion reasonable, telling New York Solicitor General Barbara Underwood, who led off the challengers' arguments, "The CVAP, Citizen Voting Age Population, is the critical element in voting rights enforcement, and this is citizen information."

But Sotomayor challenged Francisco and that theory at every turn. She is often an active questioner at the court's oral arguments, but on Tuesday her interruptions led Roberts to intervene. "Maybe you could, if you don't mind," he said to Francisco, "complete your answer."

Sotomayor has not been reluctant to invoke her personal experience or point up the impact a court ruling could have on minorities. In a similarly contentious 2014 Michigan dispute, she wrote a dissenting statement that rebuked her conservative brethren who were arguing against racial remedies such as university affirmative action. She said such measures were still needed, as was greater discussion of racial dilemmas in America.

"Race matters in part because of the long history of racial minorities' being denied access to the political process," she said, then struck what seemed to be a personal note: "Race matters because of the slights, the snickers, the silent judgments that reinforce that most crippling of thoughts: 'I do not belong here.'"

Near the end of Tuesday's arguments on the census, after lawyers for the challengers had urged the court to rule in a way that would ensure as full a count as possible, Francisco returned to the lectern and warned the justices that rejecting the citizenship question could lead to more complaints about the census form.

That could empower, Francisco said, "any group in the country to knock off any question on the census if they simply get together and boycott it."

"Are you suggesting that Hispanics are boycotting the census?" Sotomayor interjected. "Are you suggesting they don't have, whether it is rational or not, that they don't have a legitimate fear?"

Responded Francisco, "Not in the slightest, Your Honor."