On Thursday morning, President Donald Trump suggested postponing November presidential elections speculating about the potential for in-mail voting “fraud.”

In a series of tweets, Trump questioned the accuracy of “universal mail-in voting” and suggested November elections would be the “most inaccurate and fraudulent election in history” and a “great embarrassment to the USA.”

“Mail-In Voting is already proving to be a catastrophic disaster. Even testing areas are way off. The Dems talk of foreign influence in voting, but they know that Mail-In Voting is an easy way for foreign countries to enter the race. Even beyond that, there’s no accurate count!” Trump added.

There is no evidence for Trump’s claims that absentee or mail-in ballots result in widespread voter fraud.

Trump does not have the authority to change the election dates. The U.S. Constitution specifies that only Congress has the power to do that.

The tweet was the first time Trump raised a question of changing the voting date. In April, Trump denied thinking about the idea of postponing the election day. “I never even thought of changing the date of the election,” he said. “Why would I do that? November 3rd. It’s a good number. No, I look forward to that election.”

Attorney General William Barr, during his testimony before the House earlier this week, echoed Trump’s claims on in-mail voting. He said there was “a high risk” that mail-in voting would be a “massive” fraud. Despite saying he had no “reason to think” the November election would be manipulated, he still questioned the accuracy and trustworthiness of in-mail voting.

Rick Hasen, a University of California-Irvine professor and one of the nation’s top experts in election law, criticized Barr’s claims on in-mail voting fraud via Twitter on Thursday.

“Of all the ridiculous schemes that have been floated by the President or AG Barr for how mail-in ballot fraud could affect the election, the possibility of a foreign entity swaying election by mailing fraudulent absentee ballots is the most ludicrous,” Hasen tweeted.

Hasen added, “The foreign government would have to do this at scale to produce thousands of votes in even the closest swing state to try to change the outcome. With everyone watching and many states allowing voters to track their ballots this becomes impossible.”

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