MP for Ealing Southall
Assistant Whip
“A party-loyal Labour MP and government whip with very low voting attendance, who consistently backs the party while voting against several social policy reforms.”
Deirdre Costigan is a Labour and Co-operative MP for Ealing Southall, elected on 4 July 2024. She currently serves as an Assistant Whip and sits on several parliamentary committees, including the Representation of the People Bill committee and the Rare Cancers Bill committee, with prior roles on the Health and Social Care Committee and other committees during her time in Parliament.
Costigan has 100% party loyalty and a voting attendance of 16% (well below the party average of 33%), with no rebel votes recorded. Her voting pattern places her in the centre-left spectrum (38/100). On policy, she has a mixed position on Universal Credit, generally supports workers’ rights protections and trade union powers, and supports renter protections and VAT changes, while she commonly votes against expanding mental health services, tougher prison sentencing, bus services regulation, transgender rights and protest rights.
Declared financial interests include gifts, benefits and hospitality from UK sources (1 entry).
Generated 21 February 2026
How this MP participates in parliamentary votes. These numbers describe activity, not effectiveness.
How often this MP votes
Labour (Co-op) average: 33%
The percentage of parliamentary votes (divisions) this MP participated in. MPs may miss votes for legitimate reasons including ministerial duties, constituency work, or illness.
How often this MP votes with their party
Labour (Co-op) average: 99%
Estimated from voting record, not self-declared. This is a simplified model — real politics is more complex than a single axis.
6 positions
Representation of the People Bill
Since Mar 2026
Assistant Whip
Since Sept 2025
Rare Cancers Bill
Since Jun 2025
English Devolution and Community Empowerment Bill
Sept 2025 - Oct 2025
Non-Domestic Rating (Multipliers and Private Schools) Bill
Dec 2024 - Dec 2024
Health and Social Care Committee
Oct 2024 - Mar 2025
Figures include only interests with declared monetary values from the Register of Members' Financial Interests. Some categories (e.g. hospitality, overseas visits) may not have monetary values recorded, so the total may not reflect all declared interests.
Victims and Courts Bill: motion to disagree with Lords Amendment 6
AYEVictims and Courts Bill
Victims and Courts Bill: motion to disagree with Lords Amendment 5
AYEVictims and Courts Bill
Victims and Courts Bill: motion to disagree with Lords Amendment 4
AYEVictims and Courts Bill
Victims and Courts Bill: motion to disagree with Lords Amendment 3
AYEVictims and Courts Bill
Victims and Courts Bill: motion to disagree with Lords Amendment 2
AYEVictims and Courts Bill
Victims and Courts Bill: motion to disagree with Lords Amendment 1
AYEVictims and Courts Bill
Opposition Day Motion: Defence
NOOpposition Day Motion: Oil and Gas
NONational Insurance Contributions (Employer Pensions Contributions) Bill: motion to disagree with Lords Amendment 6
AYENational Insurance Contributions (Employer Pensions Contributions) Bill
National Insurance Contributions (Employer Pensions Contributions) Bill: motion to disagree with Lords Amendment 5
AYENational Insurance Contributions (Employer Pensions Contributions) Bill
National Insurance Contributions (Employer Pensions Contributions) Bill: motion to disagree with Lords Amendment 3
AYENational Insurance Contributions (Employer Pensions Contributions) Bill
National Insurance Contributions (Employer Pensions Contributions) Bill: motion to disagree with Lords Amendment 2
AYENational Insurance Contributions (Employer Pensions Contributions) Bill
National Insurance Contributions (Employer Pensions Contributions) Bill: motion to disagree with Lords Amendment 1
AYENational Insurance Contributions (Employer Pensions Contributions) Bill
Opposition day motion: student loans
NOOpposition day motion: fuel duty
NOThe percentage of votes where this MP voted the same way as the majority of their party. High loyalty is typical; most MPs vote with their party on most issues.
Rebel votes
Times this MP voted differently from the majority of their party. This can reflect independent judgement, but context matters — some rebel votes are on procedural matters, others on major policy.
