The 1923 Willesden East by-election was a parliamentary by-election for the British House of Commons constituency of Willesden East held on 3 March 1923. The constituency was a large one extending from Kilburn in the south to the Welsh Harp and on to Neasden.
Vacancy.
The by-election was caused by the resignation of the sitting Unionist MP, Sir Harry Mallaby-Deeley. Mallaby-Deeley had been MP for Willesden East since the 1918 general election. Despite the protestations of ill-health which Mallaby-Deeley cited to justify his standing down from Parliament, he lived for another 14 years during which he carried on a substantial business career. The strong likelihood is that Mallaby-Deeley was asked to stand aside and cause a by-election as a route back into Parliament for the Hon. G.F.Stanley,
Electoral history.
At the previous General Election, the constituency had become a Unionist/Liberal marginal;
! scope="col" colspan="2" style="width: 130px"|Party
! scope="col" style="width: 17em"|Candidate
! scope="col" style="width: 5em"|Votes
! scope="col" style="width: 3.5em"|%
! scope="col" style="width: 3.5em"| ;templatestyles src="Template:Tooltip/styles.css" / ;±%
! colspan="3" style="text-align: right; margin-right: 0.5em" | Majority
! colspan="3" style="text-align: right; margin-right: 0.5em" scope=row | Turnout
! style="text-align:right;" | Swing
Campaign.
Controversially in a constituency where over six thousand electors were thought to be Jewish, polling day was fixed for a Saturday.
Housing was featuring strongly as an issue of importance at this time. In the by-election at Mitcham being held on the same day as Willesden East, the Unionist candidate was Sir Arthur Griffith-Boscawen. Griffth-Boscawen had lost his seat at Taunton at the general election of November 1922 but accepted Bonar Law’s offer to remain in the government as Minister of Health while he tried to find a seat to get back into Parliament. His main task as minister was to produce a Bill on local government rating but this proved highly controversial and the issue was a magnet for a whole range of problems associated with housing, including the failure of the government to increase the number of houses being built, to be raised at Mitcham and elsewhere, including to Johnstone’s advantage at Willesden.
It was reported that the loss of the by-election would represent a blow for the Unionist government, although it was too early after the general election to see the results as a definitive verdict on Bonar Law’s administration.
Result.
The result was a gain for the Liberal Party from the Unionists with Johnstone gaining 60% of the poll and a majority of 5,176 over Stanley.
! scope="col" colspan="2" style="width: 130px"|Party
! scope="col" style="width: 17em"|Candidate
! scope="col" style="width: 5em"|Votes
! scope="col" style="width: 3.5em"|%
! scope="col" style="width: 3.5em"| ;templatestyles src="Template:Tooltip/styles.css" / ;±%
! colspan="3" style="text-align: right; margin-right: 0.5em" | Majority
! colspan="3" style="text-align: right; margin-right: 0.5em" scope=row | Turnout
! style="text-align:right;" | Swing
The Liberal victory was described by Austen Chamberlain as a “smash” and a bad omen for the by-election at Mitcham being held on the same day, which the Unionists also lost, this time to Labour. Clearly the absence of a Labour candidate at Willesden meant the Liberals were able to present Johnstone as the only progressive and anti-Tory candidate.
This tactical advantage was underscored by an unproved allegation against Stanley that he or his supporters had tried to bribe a Labour man into standing as a candidate for the purpose of splitting the Liberal vote.
The loss of Willesden by such a large majority was unexpected 
Aftermath.
It was hard to discern Willesden as part of any pattern of political success for the Liberal Party. Cook and Ramsden in their survey of British by-elections comment that none of the by-elections in the 1922-1923 Parliament pointed to the outcome of Stanley Baldwin’s Tariff reform general election of 6 December 1923. At that election, Johnstone narrowly held the seat despite the intervention of a Labour party candidate.
! scope="col" colspan="2" style="width: 130px"|Party
! scope="col" style="width: 17em"|Candidate
! scope="col" style="width: 5em"|Votes
! scope="col" style="width: 3.5em"|%
! scope="col" style="width: 3.5em"| ;templatestyles src="Template:Tooltip/styles.css" / ;±%
! colspan="3" style="text-align: right; margin-right: 0.5em" | Majority
! colspan="3" style="text-align: right; margin-right: 0.5em" scope=row | Turnout
! style="text-align:right;" | Swing
References.
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