Labour Party MP for Mitcham and Morden.
McDonagh's most significant recent act was voting against the Terminally Ill Adults (End of Life) Bill at its Third Reading in June 2025 — one of her four rebel votes on the same day against her party's majority position. She backed two safeguard amendments that would have barred applicants from qualifying if their wish to die was substantially driven by not wanting to be a burden, a mental disorder, a disability, or lack of access to care. Both amendments were defeated, and the Bill passed to the Lords without those restrictions. On assisted dying, her voting record sits 47 percentage points below her party's average in favour of access — the sharpest divergence in her profile.
Beyond that cluster of rebel votes, McDonagh is a 96% party-line voter with a participation rate of 59%, below the Commons average. Her strongest stances are on workers' rights and progressive taxation, where she votes with Labour in over four-fifths of divisions. She scores low on civil liberties (7%) and parliamentary scrutiny (12%), reflecting consistent support for government positions over amendment or oversight mechanisms. Her 152 contributions across 63 debates lean heavily toward health, the economy, and social care — consistent with her roles as chair of the APPG on Brain Tumours and the APPG for Tamils, where she has pressed ministers on research funding and human rights in Sri Lanka respectively.
McDonagh has represented Mitcham and Morden since 1997, and local coverage describes her as exceptionally active in her constituency. She sits on the Treasury Committee and the Panel of Chairs. News coverage over the past 90 days is insufficient to identify recent sentiment trends, but her longer-term press profile is strongly positive on constituency work and community representation.
Dame Siobhain McDonagh is the Labour MP for Mitcham and Morden, and has been an MP continually since 1 May 1997.
Top eight by total divisions voted, this parliament. Volume measures engagement, not direction — see Notable Votes for free-vote moments and rebellions.
Source · The Public Whip · Hansard
Moments where the whip was free, or where McDonagh broke ranks. Free votes are the truer signal of personal stance.
| Date | Bill / motion | Vote | Whip |
|---|---|---|---|
| 20 Jun 2025 | Terminally Ill Adults (End of Life) Bill: Amendment 94 | No | Freevs party |
| 20 Jun 2025 | Terminally Ill Adults (End of Life) Bill: Third Reading | No | Freevs party |
| 20 Jun 2025 | Terminally Ill Adults (End of Life) Bill: Amendment 24 | Yes | Freevs party |
Source · Hansard
“Brain cancer requires urgent innovation and cannot wait for institutions; has independently launched Margaret's trial at UCLH testing immunotherapy for newly diagnosed glioblastoma…”
“System is failing rare cancer patients; institutions resist innovation; require mandated targets for clinical trials, tissue storage expansion, and drug repurposing; government mus…”
“Emphasises that clinical trials, not just tissue freezing, are the most effective route to improved outcomes; highlights lack of NIHR funding for repurposed drug trials; launched o…”
“Advocated for more glioblastoma drug trials and sought clarity on how to access NIHR funding to expand a self-funded immunotherapy trial programme; highlighted that private fundrai…”
Select, joint and other committees McDonagh currently sits on. Committee work is where much of the line-by-line scrutiny of bills and departments happens, away from the chamber.
| Committee | Role | Type |
|---|---|---|
| Treasury Committee | Member | Select |
| Panel of Chairs | Member | Select |
Source · UK Parliament Committees API
Committee seats are where backbenchers shape legislation and hold departments to account. McDonagh sits on 2.
| Department | Qs | Share |
|---|---|---|
| Department of Health and Social Care | 2 | 25.0% |
| Foreign, Commonwealth and Development Office | 2 | 25.0% |
| Cabinet Office | 1 | 12.5% |
| Home Office | 1 | 12.5% |
| Ministry of Housing, Communities and Local Government | 1 | 12.5% |
| Treasury | 1 | 12.5% |
What assessment he has made of the adequacy of the performance of the National Institute for Health and Care Research Brain Tumour Research Consortium on improving the treatment of glioblastoma brain tumours.
The Department invests over £1.7 billion per year in research through the National Institute for Health and Care Research (NIHR).We are committed to furthering our investment in brain cancer research and have already taken steps to stimulat…read full →
Commonwealth and Development Affairs, what discussions she has had with her counterparts in Bangladesh on the (a) anti-Ahmadi protests planned in Bangladesh for 15 November and (b) upholding freedom of religion for Ahmadi Muslims and other religious communities.
The UK has a long-standing commitment to the promotion and protection of human rights, including Freedom of Religion or Belief (FoRB). We continue to support those goals through regular dialogue with the Interim Government of Bangladesh, to…read full →
If he will make an assessment of the potential impact of local authority-led initiatives to increase physical activity on public health outcomes.
The Department recognises the vital role of local authorities in promoting physical activity and continues to support them with this through the Public Health Grant, the Public Health Outcomes Framework, and by working with other department…read full →
Communities and Local Government, whether he has had recent discussions with Cabinet colleagues on taking steps to help support (a) Merton Council’s London Borough of Sport programme and (b) other local authority-led initiatives to increase physical activity.
DCMS, as the lead department for the Government's arm's-length body Sport England, is investing up to £250 million of National Lottery and Exchequer funding into more than 90 locations across England. This investment is being delivered in p…read full →
No active register entries.
| Category | £ | Share |
|---|---|---|
| Staffing | 256,100 | 86.6% |
| Office Costs | 39,609 | 13.4% |
| Total · 106 claims | 295,709 | 100% |
Source · IPSA · FY 24_25
Nothing tabled for McDonagh on the published Order Paper this week.
| Year | Constituency | Votes | Share | Result |
|---|---|---|---|---|
| 2024 | Mitcham and Morden | 25,085 | 55.4% | Won |
| 2019 | Mitcham and Morden | 27,964 | 61.1% | Won |
| 2017 | Mitcham and Morden | 33,039 | 68.7% | Won |
| 2015 | Mitcham and Morden | 27,380 | 60.6% | Won |
| 2010 | Mitcham and Morden | 24,722 | 56.5% | Won |
| Candidate | Votes | % | |
|---|---|---|---|
| Siobhain McDonaghWON | Lab | 25,085 | 55.4 |
Showing the MP’s own row only. Full result table: see Mitcham and Morden →