President Donald Trump stood in the well of the House chamber on the penultimate night of January and spoke about undocumented immigrants with his familiar rhetoric.

During his first State of the Union address, the “America first” president lambasted the country’s immigration laws, saying they have for too long “allowed drugs and gangs to pour into our most vulnerable communities,” cost poor Americans jobs, and “caused the loss of many innocent lives.”

Trump — along with his chief of staff and top domestic policy adviser — often draws a direct line between undocumented immigrants and crime, drugs and even terrorism. But there is one alleged case of illegal immigration the president and his senior staff rarely discuss — though it hangs over his brash rhetoric and policy proposals.

Slovenian-born Melania Trump watched as her husband spoke those words from her spot in the House gallery. Her own immigration history has never been fully explained by the Trump camp, even after reports during the homestretch of the 2016 campaign that raised the possibility she was, for a time, in the United States illegally.

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Melania Trump looked on as the president pointed out the parents of two teenage girls from Long Island who were allegedly killed by MS-13 gang members. “Tonight, I am calling on the Congress to finally close the deadly loopholes that have allowed MS-13, and other criminals, to break into our country,” her husband said.

“The United States is a compassionate nation,” he said, adding his “highest loyalty, my greatest compassion, and my constant concern is for America’s children, America’s struggling workers, and America’s forgotten communities. I want our youth to grow up to achieve great things. I want our poor to have their chance to rise.”

The implication was clear: Undocumented immigrants are a scourge on the U.S. economy, a threat in the country’s most vulnerable communities and a hindrance to upward mobility. In short, the president — often joined by Chief of Staff John F. Kelly and chief domestic policy adviser Stephen Miller — sees illegal immigrants as a threat to the “American dream.”

Watch: The State of the Union in 3 Minutes

An immigrant’s story

But he and his team have never thoroughly addressed the curious case of then-Melanija Knavs, who at 26 moved to New York City in the mid-1990s to pursue a professional modeling career. It would be two years before she met and began dating businessman Donald Trump. And still unresolved is whether she and her modeling agency properly handled her immigration status during that window.

At issue are 10 modeling jobs in the United States she allegedly was paid for in 1996 before she was granted legal authorization to work in the country, according to a 2016 Associated Press report. The news agency obtained what it described as “detailed accounting ledgers, contracts and related documents from 20 years ago,” which were the basis of a Nov. 5, 2016, article.

As a presidential candidate, her now-husband regularly railed against employers who violate federal laws that prohibit paying undocumented immigrants. But what about Melania, who received her green card in 2001 and became a naturalized U.S. citizen five years later, according to Trump’s 2016 presidential campaign organization?

The first lady and the Trump organization always have denied that she violated her immigration status. “Let me set the record straight: I have at all times been in compliance with the immigration laws of this country. Period,” she tweeted on Aug. 4, 2016, amid questions about her status in the mid-1990s.

pic.twitter.com/U3VTY05mzc

— MELANIA TRUMP (@MELANIATRUMP) August 4, 2016

In 2016, the AP requested Michael J. Wildes, a New York attorney whom Melania Trump had asked to review her immigration documents, to examine the 1996 payment papers from the shuttered modeling agency, Metropolitan International Management. He responded to the news service with only a brief statement, saying, “These documents, which have not been verified, do not reflect our records including corresponding passport stamps.”

A White House spokeswoman did not respond to a request for comment.

Private papers

During Trump’s successful presidential bid, there were calls for the campaign organization to release his wife’s immigration documents to settle the matter once and for all. Those documents remain private.

What’s more, “the Trump campaign promised a press conference on the issue, and promised to clear up the whole thing,” David Leopold, a Cleveland-based immigration lawyer, told Roll Call last week. “But, of course, that press conference never happened. And they have never cleared it up.”

“It’s fair to question her immigration background because of her husband’s rhetoric on illegal immigrants and his policy proposals,” Leopold said. “Melania’s immigration history wouldn’t be relevant but for the president’s attacks on ‘Dreamers’ and foreign nationals and him calling Africa and Haiti ‘shithole countries.’” (The president has denied saying those words, though multiple lawmakers report he did.)

Theresa Cardinal Brown, a former senior Department of Homeland Security immigration official in the George W. Bush administration, offered a simple explanation on the question of why the president has not directed his aides to release his wife’s immigration documents or publicly explain her history.

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“I just don’t think he believes she was ever undocumented or here illegally,” said Brown, now with the Bipartisan Policy Center. “If he doesn’t think that, there’s no inconsistency in his mind. That’s how the president thinks: The lawyers they paid to handle this signed off, so any questions have been answered. End of story.”

On the specifics of Melania Trump’s case, Brown said it merely “shows the immigration system is enormously complicated,” adding people and firms for which they work “push the envelope of the rules every single day.”

But would changes to the legal immigration system the White House has proposed as part of an overhaul framework that Trump wants to serve as a starting point this week, when the Senate is slated to begin floor debate on the issue, simplify things for people like Melanija Knavs? “There’s nothing he’s proposed that would do that,” Brown said.

Leopold criticized the president over the matter, arguing he is taking a “what’s-good-for-my-family-isn’t-good-for-the-country approach.” He wants the White House to explain whether the first lady “misrepresented herself to immigration officials” or “didn’t play by the rules.”

“These are just a few questions that should be answered,” he said. “They should open her file and make it public.”