The truth behind Trump’s biggest illegal voter claim

The message was addressed to “REAL AMERICAN PATRIOTS” to ensure a victory “TOO BIG TO RIG!”

Sent out to a mailing list by the Republican National Committee co-chair Lara Trump, it combined two of the biggest themes of Donald Trump’s campaign: immigration and alleged election fraud.

“Experts are saying that as many as 2.7 million illegals could vote in November,” read the email from Ms Trump - the former president’s daughter-in-law.

But the number they cite is derived from a decade-old survey that has been heavily disputed.

Trump and his allies frequently makes non-specific claims about both immigrants and alleged dirty tricks by the Democratic Party.

And while there is some clear evidence that some immigrants are registered to vote, it’s equally clear that the 2.7 million figure is a huge exaggeration.

The roots of the statistic are found in an article, “Do non-citizens vote in U.S. elections?”, published in the journal Electoral Studies in 2014.

Written by three academics led by Jesse Richman, an associate professor at Old Dominion University in Virginia, the paper says the "number of non-citizen voters… could range from just over 38,000 at the very minimum to nearly 2.8 million at the maximum.”

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Mr Richman and his colleagues did not comb through voter rolls or personally survey immigrants to come to that conclusion, but instead relied on a data set from a long-running Harvard-backed survey called the Cooperative Election Study (CES).

The CES included a number of people who self-identified as non-citizens and indicated that they had voted in the 2008 and 2010 elections.

But the people behind CES have repeatedly rejected the conclusions of Mr Richman's paper, which attracted controversy and attention before and after the 2016 presidential election.

Brian Schaffner, a Tufts University professor who is one of the CES co-principal investigators, told the BBC that it’s not possible to draw statistical conclusions from a relatively small number of survey participants.

The CES is intended to be a survey of legal voters, and only 339 out of the nearly 34,000 in the 2008 survey said they were non-citizens. That does not constitute a representative sample of the population, Schaffner said.

Various respondent errors and further variables may have also affected the accuracy of that data pool, he added.

In recent years, the CES has included more detailed questions about citizenship and registration to increase its accuracy.

Mr Richman, the author of the Electoral Studies article, drew on that data to conclude in 2023 that 1% of non-citizens were registered to vote. He further estimated half of that number voted in the 2022 midterm elections.

But the CES survey officials maintain that their study is not suitable to create an estimate of non-citizen voting.

The non-citizen voter claims were given new life in May 2024, when a pro-Trump fact-checking organisation, Just Facts, published a blog post headlined: “Study: 10% to 27% of Non-Citizens Are Illegally Registered to Vote”.

The post asserted that “roughly 1.0 million to 2.7 million [immigrants] will illegally vote” in November’s election.

The claim went viral in right-wing spaces online, and were spread by news sites and conservative influencers. Elon Musk, who has repeatedly posted misleading messages about immigrants and voting to millions of his followers, shared this post as well.

When contacted by the BBC, Just Facts founder James Agresti said he stands by his conclusions, although he characterised the Trump campaign claim as a “half truth, because the study has sizable margins of uncertainty”.

Mr Richman’s figures, including his recent estimate that 1% of non-citizens are registered to vote, should be viewed as a minimum, Mr Agresti said.

He claimed that the true scale could potentially be much higher.

There is another problem with the argument that large numbers of immigrants are voting: there are very few confirmed cases of it.

The right-wing Heritage Foundation think tank compiled a database that includes decades of voting fraud cases. But only about 100 include a reference to non-citizens voting.

Criminal prosecution of illegal voters - not just non-citizens, but felons and other ineligible voters - are also extremely rare.

Despite a now decade-long obsession with illegal voting, those numbers have not dramatically risen. Investigations into voter rolls show very few immigrants registered to vote and even fewer voting.

Conservatives, Trump supporters, and some scholars such as Mr Richman, allege that there are so few prosecutions because illegal voting is considered to be a minor crime by many. They say that authorities have spent few resources investigating it in the past.

Still, recent searches of active voter rolls - largely inspired by Trump and Republican Party officials - has turned up a relatively small number of illegal voters.

Mr Richman conducted a survey of Arizona's 4 million voter records and found between 1,934 and 6,480 non-citizens registered to vote.

Earlier this year, the office of Ohio’s Republican Secretary of State Frank LaRose - a Trump supporter - examined around 8 million registrations and found around 600 people on the state’s voter rolls who could not prove their US citizenship.

The state also struck an additional 155,000 registrations from the rolls, largely because of address changes.

Other states, including New Jersey and Virginia, have also removed hundreds of voters from their rolls in recent years - but the totals have not come close to the 10-to-27% figure cited in the Just Facts blog post.

The empirical evidence shows that a small number of non-citizens are registered to vote - and the number who vote is even smaller.

And then the number of immigrants who do not have legal permission to be in the US - the "illegals" in Lara Trump's email - is even smaller.

The BBC contacted the Trump campaign and the Republican National Committee for comment.