Donald Trump really wants you to believe that the election is rigged — and he’s citing voter fraud as proof.

Of course there is large scale voter fraud happening on and before election day. Why do Republican leaders deny what is going on? So naive! — Donald J. Trump (@realDonaldTrump) October 17, 2016

Trump’s claim is simply baseless — voter fraud is extremely rare. Loyola Law School professor Justin Levitt has tracked credible allegations of in-person voter impersonation for years, finding 35 total credible allegations between 2000 and 2014, when more than 800 million ballots were cast in national general elections, and hundreds of millions more were cast in primary, municipal, special, and other elections.

There are other kinds of potential voter fraud, such as vote buying, insider ballot-box stuffing, double voting, and voting by people who turn out to be ineligible. But all of these are also extremely rare, and there’s no evidence that they have swung national elections, according to experts (and even Breitbart, a pro-Trump outlet).

Voter fraud has long been a hobbyhorse of conservative media. It’s one of the reasons Republicans at the state level have proposed strict voter ID laws. But it’s unusual for a presidential candidate to make it a focus of his campaign, especially with allegations — before the election is even held — that large-scale voter fraud will rig the election in his opponent’s favor.

Yet Trump has advised his supporters to pose as election monitors on Election Day. And some are taking him up on that. One Trump supporter told the Boston Globe:

“I’ll look for … well, it’s called racial profiling. Mexicans. Syrians. People who can’t speak American,” he said. “I’m going to go right up behind them. I’ll do everything legally. I want to see if they are accountable. I’m not going to do anything illegal. I’m going to make them a little bit nervous.”

This is extremely alarming. As Jamelle Bouie wrote for Slate, America has a very long history of intimidating voters — particularly minority voters — at the polls on Election Day. These type of voter suppression tactics were used explicitly to block the voice of racial minorities. Now, they’re being used for effectively the same cause — except out of fear, apparently, of voter fraud.

But this fear shouldn’t exist in the first place. Voter fraud is incredibly rare, and it doesn’t swing national elections. Worries about it should never lead to Americans silencing fellow voters on Election Day.

Watch: Why voting in 2016 could be nearly impossible for some Americans

Correction: This article originally misestimated the percent of votes that were fraudulent from 2000 to 2014.