Liberal Democrat defector Sarah Wollaston was tonight accused of hypocrisy after it emerged she had lobbied for automatic by-elections for MPs who switch parties, despite refusing to face one herself.

The former Tory MP, who defected to Change UK in February, before joining the Liberal Democrats on Wednesday defied calls to go back the polls in Totnes.

She claimed her constituents, of whom only 13 per cent voted Lib Dem at the 2017 general election, did not want a Conservative candidate but a “centrist” MP.

She said: “Many of my constituents have been rather horrified by the way the Conservative Party have shifted to the right.

"And I was selected originally by a fully open postal primary, the first in the country, so I think that people do have a support across my constituency for that kind of centre ground approach."

The Lib Dems were backed by just a quarter of the numbers of voters who voted for the Tories in Totnes two years ago - although the Lib Dems consistently finished second to the Conservatives in the constituency until their vote share collapsed following the 2010 coalition.

In 2011, Dr Wollaston, a former GP, supported a 10-minute rule bill that proposed that any colleague who had crossed the floor “should trigger an automatic by-election so that their constituencies can have the final say on their decision”.