1955 Mid Ulster by-election
The by-election held in Mid Ulster on 11 August 1955 was called as a result of a vote in the British parliament on 18 July 1955 which voted 197 votes to 63 to nullify the result of the previous 1955 UK General Election in the constituency. Mitchell won again but lost the seat to Charles Beattie after an election petition, with Beattie also being disqualified shortly after for holding an office of profit. This led to the 1956 Mid Ulster by-election.