Migrant families seeking asylum from Honduras and Guatemala walk down a dirt road after crossing the Rio Grande into the United States from Mexico in Penitas, Texas, in January 2019.Adrees Latif / Reuters

Exactly where President Donald Trump was getting the illegal-immigration numbers he tweeted on Sunday morning was anyone’s guess. His acting chief of staff, appearing a short while later on CBS’s Face the Nation, couldn’t say. But the timing of his tweets suggests a play to shore up support among hard-liners who have excoriated him for caving on Friday to Democrats and ending the partial government shutdown without securing a dollar for his wall along the southern border. Ann Coulter, Representative Steve King of Iowa, and other right-wing figures had blasted the president’s immigration proposal last week as “amnesty.” Perhaps, as negotiations commence during a three-week shutdown reprieve, Trump wanted to signal his continued devotion to their cause.

To be sure, the millions of people living in the United States without authorization present a major policy issue that both parties have grappled with for decades. But ever since Trump made illegal immigration the central focus of his campaign, he’s been citing statistics that are inflated, misrepresented, or even invented. On Sunday he took his flights of fancy to a new high as he mischaracterized Texas voter data and made a claim about undocumented immigrants that contradicts his own Department of Homeland Security.

“There are at least 25,772,342 illegal aliens, not the 11,000,000 that have been reported for years, in our Country,” he wrote in the second of five Sunday-morning tweets on the subject. While it’s impossible to precisely count unauthorized immigrants, informed estimates have consistently placed the level at less than half of Trump’s figure. Just last month, the DHS’s Office of Immigration Statistics released its latest appraisal based on Census Bureau data: “DHS estimates that 12.0 million illegal aliens were living in the United States in January 2015.” Unless the undocumented population somehow increased by more than 100 percent in three years, Trump’s figure isn’t close to being accurate.

Outside government, the nonpartisan Pew Research Center estimated there were 10.7 million unauthorized immigrants in 2016. Even FAIR, the hard-line immigration group that supports Trump’s agenda, pegged the number at “approximately 12.5 million” in 2017. Date-restricted internet searches did not turn up earlier references to the president’s specific figure. He also claimed that illegal immigration thus far in 2019 has cost the country “$18,959,495,168.” Trump wildly inflates even the largest estimates of such costs, but his use of supposedly exact figures prompted The Washington Post’s chief fact-checker, Glenn Kessler, to write, “Nothing screams fake numbers [louder] than false precision.”

The president’s acting chief of staff, Mick Mulvaney, nonetheless defended his boss’s claim on Face the Nation. “I’m not exactly sure where the president got that number this morning,” he said, but he argued that the total may have grown because people kept entering the country illegally in recent years. However, this ignores the net decline over that same period as more unauthorized immigrants depart than arrive, especially among Mexicans.

Mulvaney also said he has “seen ranges as high, I think, as 30 or 40 million.” While reputable estimates based on census data consistently put the number at about 11 million, a demographic simulation last year by Yale University business-school professors came up with a theoretically predicted range of 16 million to 29 million. That study drew extensive coverage in conservative media but widespread rejection among subject-matter experts; the nonpartisan Immigration Policy Institute called it a “thought experiment … based on seriously flawed assumptions,” such as applying border-crossing trends from one period to other periods that did not have comparable data.

Hard-liners argue that illegal immigration poses a threat not just to the country’s economy and culture but also to its democratic process. Trump fed that concern with another Sunday-morning tweet that mischaracterized Texas voter data reported Friday: “58,000 non-citizens voted in Texas, with 95,000 non-citizens registered to vote,” he tweeted an hour after the topic appeared on Fox & Friends, the chummy morning talk show he often watches.

As The Texas Tribune explained, the Texas secretary of state’s office compiled a list of 95,000 registered voters who at one point provided documentation such as a green card or a work visa suggesting that they were not citizens. Of that group, the state said 58,000 had voted at least once from 1996 to 2018.

However, the office used capital letters in a notice to county officials, emphasizing that the names should be considered “WEAK” matches. In many cases, immigrants may have registered and voted after becoming citizens, as is their right, so these numbers alone don’t prove any illegal voting at all. “People get naturalized,” Chris Davis, the president of the Texas Association of Elections Administrators, told the Tribune. “It’s entirely too early to say that” 58,000 non-citizens voted. In other cases, the matches may be false positives, as in 2012, when a controversial effort by Florida’s Republican leaders questioned the citizenship of a Brooklyn-born World War II veteran.

Yet the president seized on the report in support of his long-held but never-substantiated claim that voter fraud is rampant in America. “These numbers are just the tip of the iceberg,” he tweeted. “All over the country, especially in California, voter fraud is rampant.” Trump has a long history of casting doubt on the integrity of U.S. elections, most notably claiming that the only reason he lost the popular vote in 2016 by 2.9 million ballots was “the millions of people who voted illegally.” There are isolated cases of illegally cast ballots; for example, a Mexican-born permanent legal resident in Texas was convicted of voter fraud last year. But as PolitiFact documented and numerous investigations have concluded, there is no evidence of widespread illegal voting in the United States.

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