Vice President Pence vouched Tuesday for President Trump’s dubious, unfounded claim that Middle Easterners are headed to the U.S.-Mexico border as part of the caravan that started in Honduras.

But to do so, he had to use a previously debunked statistic that directly contradicts his own administration.

Answering a question about Trump’s claim at a Washington Post Live event, Pence said it was “inconceivable that there are not people of Middle Eastern descent” in the caravan. He then expounded:

In the last fiscal year, we apprehended more than 10 terrorists or suspected terrorists per day at our Southern border from countries that are referred to in the lexicon as “other than Mexico” — that means from the Middle East region. The idea that they would not be in this large throng ... 

Pence then trailed off and talked about his contacts with Central American leaders and about human trafficking. But the claim is a strong one. If there are indeed 10 terrorists or suspected terrorists arriving at the southern border every day — no matter how you define “suspected terrorist” — it would lend credence to the idea that Middle Easterners and even terrorists could be using the caravan as a Trojan Horse.

Unfortunately for Pence, the stat quickly falls apart upon further inspection. Pence used it in February when it was supposedly seven terrorists or suspected terrorists being apprehended daily at the southern border. PolitiFact tried to find any substantiation for the claim and found none. It gave Pence “Pants on Fire” — its worst rating for a claim.

Where PolitiFact did find something similar was when it came to total terrorists or suspected terrorists that the Department of Homeland Security prevented from entering at all ports of entry. Here’s a joint report from DHS and the Justice Department from January, shortly before Pence made the “seven” claim:

...In 2017 alone DHS had 2,554 encounters with individuals on the terrorist watch list (also known as the FBI’s Terrorist Screening Database) traveling to the United States.

That number — 2,554 — works out to almost exactly seven per day. But, again, it is not specifically about the border, which is what Pence has claimed.

Further undermining Pence’s claim is the head of DHS herself. In June, Secretary Kirstjen Nielsen used a “10 per day” stat for terrorists and suspected terrorists trying to enter the United States. But just like the DHS/DOJ report, she wasn’t talking about the Southern border.

“In fact, on average, my department now blocks 10 known or suspected terrorists a day from traveling to or attempting to enter the United States,” Nielsen said.

So how could there be 10 known or suspected terrorists being apprehended at the southern border if there are 10 total known or suspected terrorists trying to enter through all ports of entry? That would mean no terrorists attempting to use other ports of entry, including flying to airports. That’s just not true.

In fact, if 10 known or suspected terrorists are trying to enter the United States per day, it stands to reason that the vast majority of them are not using the southern border, given all the other options and the arduousness of crossing the border. In addition, Pence says these people were “apprehended,” which isn’t even what the DHS/DOJ report and Nielsen are saying; some of these people may not have been allowed to board flights to the United States in the first place because they were on the terrorist watch list.

Update: In a statement to The Post, Pence spokeswoman Alyssa Farah tacitly acknowledges that Pence misstated the stat, and that it’s actually for all ports of entry. “In 2017 alone the U.S. apprehended on average between 10 suspected terrorists a day attempting to enter the country illegally. And those are just the ones that we catch. It’s inconceivable that this caravan — which is being broadcast around the globe — hasn’t already been infiltrated by individuals with ties to extremism.”

And perhaps the strongest contradiction of Pence’s claim comes from the Trump administration’s own State Department. In July 2017, it issued a report that said there was “no credible information that any member of a terrorist group has traveled through Mexico to gain access to the United States.”

Not 10 per day. None.