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Postal Ballots and Survey Bias
There was no “dodgy postal vote spike” in the 2019 Election.
After the 2019 General Election, claims spread that postal voting had surged.
These claims are false. Electoral Commission statistics shows postal voting fell between 2017 and 2019.
The claim originated from an Ashcroft-badged post-election survey. These surveys overestimate postal voting. This systematic error arises due to the survey’s design.
A survey estimate of 38%
On Christmas Eve, Prof Grayling (NCH) wrote there was a “dodgy postal vote spike”. About 3,000 Twitter users shared that post:
Another Twitter post on the same day asserted:
The postal vote was 37%. In previous elections the postal vote never got out of the teens!
The claim comes from the Lord Ashcroft Polls-badged post-election survey¹. In his initial analysis, Lord Ashcroft wrote:
We found 38% saying they had voted by post.
That paragraph was later removed.
