The Trump administration's executive order addressing the collection of citizenship data doesn't mention Justice Samuel Alito's dissent in the recent U.S. Supreme Court census case. But one of his footnotes may have provided some inspiration as officials looked for reasons justifying the gathering of that information.

A comparison of Trump's executive order, and the Supreme Court's decision blocking the administration from adding a citizenship question, revealed one primary similarity: Alito's first footnote.

Alito was on the losing side of the Supreme Court's census ruling, and he wrote a dissent that argued federal judges should not play any role in reviewing the U.S. Commerce Department's reasoning for including a citizenship question on the census. “No one disputes that it is important to know how many inhabitants of this country are citizens,” Alito wrote in his opening lines, to which he attached a footnote.

That footnote said: “As a 2016 Census Bureau guidance document explained, obtaining citizenship statistics is 'essential for agencies and policy makers setting and evaluating immigration policies and laws, understanding how different immigrant groups are assimilated, and monitoring against discrimination.'”

Trump's executive order, which said agencies must collaborate to provide records showing citizenship status information, identified four reasons why the government wants to ensure “that the department has available the best data on citizenship that administrative records can provide.”

The first reason pointed to the Census Bureau guidance that Alito quoted in his footnote. Trump's executive order stated: “The Census Bureau has long maintained that citizenship data is one of the statistics that is 'essential for agencies and policy makers setting and evaluating immigration policies and laws.'”

The document that Alito noted in his footnote was not referring to the census itself, but to a different survey tool employed by census officials. When the Justice Department asked the Supreme Court to take up the citizenship question case, after losing a trial court ruling in New York, the petition did not identify the survey that Alito noted.

Alito's footnote caught the attention of several legal scholars, including Marty Lederman, an Obama-era Justice Department lawyer who now teaches at Georgetown University Law Center. Lederman predicted on Twitter recently that the Trump administration might try to use Alito's footnote as part of any new effort to argue in support of adding a citizenship question after the Supreme Court's ruling last month.

Although he didn't think Trump's reasons in the executive order should have prevailed if they had been offered in the census litigation, Lederman tweeted on Thursday: “But they would have had a much better shot going with them—and in hindsight almost certainly would have prevailed.”

Instead, the Commerce Department argued throughout the federal court litigation that the citizenship question was necessary for enforcement of the Voting Rights Act. The Supreme Court majority called those justifications “contrived.”

“We cannot ignore the disconnect between the decision made and the explanation given,” Chief Justice John Roberts Jr. wrote for the majority, joined by the court's liberal members.

Sam Alito Justice Samuel Alito testifying before Congress earlier this year. Credit: Diego M. Radzinschi / ALM

Alito didn't think the Supreme Court had any business questioning what Commerce Secretary Wilbur Ross said—or did not say—were his real motivations for asking census respondents to say whether they are living in the country as a citizen. In his 20-page dissent, Alito called the majority decision “regrettable.”

“To put the point bluntly, the federal judiciary has no authority to stick its nose into the question whether it is good policy to include a citizenship question on the census or whether the reasons given by Secretary Ross for that decision were his only reasons or his real reasons,” Alito wrote.

Trump, appearing with U.S. Attorney General William Barr on Thursday in the Rose Garden, announced the administration would give up its effort to put a citizenship question on the census. Lawyers involved in the litigation, including Dale Ho, who leads the voting rights team at the American Civil Liberties Union, declared victory. “It's official. There will be NO citizenship question on the 2020 census. It's over. We won,” Ho said in a tweet.

The census executive order the Trump administration issued Thursday wasn't the first to cite a Supreme Court justice.

In 2017, just weeks after taking office, Trump signed an environmental-law order that included a direct reference to the late Justice Antonin Scalia. The order, limiting the scope of what environmental regulators would consider the “waters of the United States,” directed the U.S. Environmental Protection Agency to revise the federal waters rule “in a manner consistent with the opinion of Justice Antonin Scalia” in the case Rapanos v. United States.

Scalia wrote the 2006 plurality opinion for the high court. Alito's dissent in the census case was joined by no other justice.