This claim, by philosopher and author AC Grayling, about 1.1 million Brexit postal ballots being missing or rejected is similar to a number of other tweets shared in recent days.
(Update: since this piece was published Mr Grayling has said he was asking a question, rather than making a claim.)
All of them seem to make claims originating in data from the Electoral Commission showing that around 975,000 postal votes were not returned during the EU referendum, with roughly 170,000 further ballots rejected.
This seems to be the 1.1 million postal ballots Mr Grayling discusses in his tweet. But while the data is correct, the votes aren’t recorded as “missing”—instead about 975,000 ballots sent out by the Electoral Commission were not returned to it.
There are many reasons why someone may not return a postal vote: for example they may have forgotten to do so, or chosen not to vote.
As for the roughly 170,000 rejected ballots, most were rejected due to problems verifying the voter—either no information on this was provided, or it didn’t match information held by the Returning Officer—and some ballots may have been returned empty.
Separate to this, a further 21,000 ballots were returned after polls closed (and therefore ineligible), and around 23,000 were returned to the Electoral Commission as undelivered.
Overall, 86% of the 8.5 million postal ballots issued during the EU referendum were counted in the final vote. That’s a higher percentage than at the last two UK general elections (the rate was 83% in both).
There is no evidence that postal votes were mishandled
Mr Grayling alludes to postal votes being handled by a firm whose director is a former Conservative MP in favour of Brexit. We’ve seen no evidence that postal votes were manipulated by the companies handling them.
Presumably Mr Grayling is referring to former Conservative MP Peter Lilley, who was at the time of the EU referendum a board member of a company called IDOX. IDOX describes itself as "the largest electoral services provider in the UK", and provides postal vote management software.
The company was invited to tender for contracts with the Electoral Commission during the referendum. The Electoral Commission also said that any Local Counting Officers that had a contract with IDOX “will have used their services to support them with the delivery of elements of the poll, such as the administration of the postal vote process and the production of registers for use in polling stations”.