US election 2020: Do postal ballots lead to voting fraud?

President Trump has criticised the expansion of postal voting in the presidential election, claiming it leads to widespread fraud - but what evidence is there?

The US is in uncharted territory during the coronavirus pandemic with a record number of Americans voting by post.

Election authorities and the postal service have been put under immense strain processing the millions of extra ballots.

This has led to claims the system is unsafe and susceptible to manipulation.

Numerous national and state-level studies have shown that although there have been isolated cases, electoral fraud is very rare.

There have been a few, well-publicised cases, such as in the 2018 North Carolina primary, which was re-run after a consultant for the Republican candidate tampered with voting papers.

But the rate of voting fraud overall in the US is less than 0.0009%, according to a 2017 study by the Brennan Center for Justice.

And Federal Election Commission head Ellen Weintraub has said: "There's simply no basis for the conspiracy theory that voting by mail causes fraud."

Let's look at some specific examples where fraud has been claimed this year.

Virginia

Speaking at a rally in mid-October, Donald Trump said: "In Virginia, 500,000 applications were made that were false."

And these applications, to apply for an absentee ballot form, were sent out with the wrong return address.

But the electoral authorities in Virginia say there was no fraudulent intent and the mistake has been corrected.

The Virginia Center for Voter Information (CVI) said: "We worked for weeks to make sure that no Virginia voter was inconvenienced as a result of our printing error."

And as of 19 October, 300,000 registered voters have since returned an application for an absentee ballot, the CVI reports.

Ohio

President Trump tweeted:: "In Ohio, 50,000 ballots were wrong, fraudulent - 50,000."

And about 50,000 voters did receive the wrong ballot in the post, in Franklin County, Ohio, in early October.

But there is no evidence this was done fraudulently.

And the local elections board says everyone affected has now been sent the correct voter slip, with safeguards in place to ensure no-one votes twice.

The board said the ballot error had been a "serious mistake".

But in response to the president's tweet, it added: "Our board is bipartisan and our elections are fair.

"And every vote will be counted."

But these were all isolated incidents.

And there remains overwhelming evidence that voting by post is safe and secure.

There are provisions in place to prevent people from impersonating voters or stealing ballots - such as authorities checking that ballots have come from voters' registered address and requiring signatures on envelopes.

These safeguards are being applied to all postal votes.

Ballot collection, when one person submits completed ballots on behalf of a group of voters for reasons such as old age or ill-health, is legal in 26 states.

But there are limits on how many ballots one person can deliver.

For example, in Minnesota, a third party can collect only three ballot papers.

Done on a larger scale, in a potentially illegal fashion, it's known as "ballot harvesting".

And there have been accusations of ballot-harvesting fraud in Texas and Minnesota.

But these remain unproven.

Although there has been very little evidence of actual fraud, the unprecedented expansion of postal voting in these elections suggests there may well be serious capacity issues ahead.

President Trump has stepped up the pressure, by warning his millions of followers on social media of "big problems and discrepancies with mail-in ballots all over the USA".

"Must have final total on 3 November," he added.

But the counting of votes, including the high volume of postal ballots, means it could take significantly longer than that.

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