How the Green Party Tripled in Size Without the Paper Trail to Match

In August 2025, the Green Party of England and Wales held a leadership ballot and got 64,581 registered voters. Eight weeks later, the membership had passed 140,000. And by the end of November, it had exceeded 180,000.

Somewhere between those numbers, the party’s own constitutional watchdog was forced to halt a separate selection process and declare the membership records ‘not as good as we would like’.

This is the story of how that gap opened.

The Headline Numbers

The August 2025 ballot was locked to a voter base of 64,581. The result was decisive on that specific basis. Zack Polanski took 84.1 per cent of the vote on a 37.6 per cent turnout, translating to exactly 24,265 votes cast. By late October, The Guardian reported the membership had hit 140,000. Less than a month later, the Green European Journal put the figure above 180,000.

That leaves a strict eight-week gap between a clean, functioning electorate and a membership base that had nearly tripled. The official record does not explain where those missing tens of thousands of members sat while the ballot took place.

The Bureaucracy That Was Already Failing

The administration was buckling before the surge arrived.

A motion at the Autumn 2023 conference postponed the scheduled 2024 leadership election. That delay compressed years of factional pressure into a single unstable window.

The enforcement tier was already running out of capacity. The Disciplinary Committee, which handles internal complaints, routinely failed to publish minutes. Suspensions dragged on for months or years. The internal blog Greens in Exile flagged this pattern as a severe backlog.

Vacancies opened up in the oversight layers.

Simon Stafford-Townsend resigned from the South West seat on the Green Party Regional Council in April 2024. The November 2024 Annual General Meeting drew just 418 attendees, representing less than 0.8 per cent of the party at the time.

The paperwork points to a dispute that was buried rather than solved. A dissenting Disciplinary Committee Minority Report was deferred at that November AGM. The Spring 2025 conference was then cancelled entirely. The compliance debate never reached a vote before the leadership race began.

The Polanski Bid and the Shape of the Surge

Carla Denyer announced in May 2025 that she would step down as co-leader. Polanski launched a solo bid immediately. He ran on an ‘eco-populist’ platform aimed directly at younger voters and the disaffected left. The response was digital and instantaneous.

Leaked internal data cited by Novara Media showed the party jumping from roughly 60,000 to over 65,000 members in a matter of weeks in early June 2025.

This was the second-largest growth month the party had ever recorded. The legacy infrastructure, built for slow community recruitment, was suddenly catching thousands of online applications with no obvious way to vet them.

The Disclosure Directive

Novara Media reported on a leaked directive from the Internal Returning Officer, the official overseeing the ballot, dated late June 2025. According to the leak, this directive banned party officers from disclosing membership figures during the contest.

The press office defended the blackout. They issued a statement calling for transparency on the figures ‘optional’ and confirmed they would ‘side-step’ disclosure until the vote was over.

This directly clashes with the party’s public campaign mandate of open democracy and grassroots accountability. A mass movement was supposedly building, but the central office actively classified the official data.

The written rationale memorandums from the internal returning officer for this period are absent from the public record. We have the leaked reporting of the directive, but the specific constitutional clause used to justify the data restriction remains entirely unknown.

The Ballot That Was Held on the Old Numbers

The party set a strict 31 July 2025 cut-off for new members to qualify for the leadership vote. That line formally divided the eligible from the ineligible.

At the start of August, the registered voter base was locked at 64,581.

The election proceeded smoothly on this contained base, returning 20,411 votes for Polanski, 3,705 for Ramsay-Chowns, and 149 for re-opening nominations. The digital onboarding portal lacked a documented manual approval gateway.

The central technical question of how those 64,581 voters were credentialled before receiving their ballots remains completely unanswered.

The September Audit

On 22 September 2025, the Standing Orders Committee (SOC) intervened in a separate internal process. They paused the House of Lords selection, invoking clause 5(xxi) of the constitution.

The official ruling formally described the selection as ‘severely flawed’. The author of the Greens in Exile blog independently characterised the governance situation as an ‘omnishambles’.

The SOC’s actual text diagnosed a deep structural failure. They ruled that the membership records were ‘not as good as we would like’ and noted a complete lack of clear paper trails for decision-making.

The ruling reached the public through a critic’s blog rather than the party’s own site. The records were declared unreliable in writing by the party’s own watchdog, yet this finding did not trigger a wider audit of the membership database at the time.

The Second Wave the Bureaucracy Could Not See

By October 2025, the membership hit 140,000. It passed 180,000 in November, overtaking both the Conservatives and the Liberal Democrats on individual membership.

Local branches broke under the physical strain. The Guardian reported on one association that swelled from around 400 to over 1,000 members in weeks. They had previously booked meeting rooms with a 50-person capacity.

The central party admitted to collecting ‘limited data on the background of new members’. The onboarding process was no longer a vetted entry point. It was an automated funnel taking in names and payments.

There is no centralised audit log visible in the unprivileged record reconciling that 180,000 figure against the Electoral Commission’s permissible donor register.

The Political Result on a Failing Spine

The raw numbers translated into electoral power on 26 February 2026. Hannah Spencer won the Gorton and Denton by-election with 40.7 per cent of the vote, securing a 27.5 percentage-point swing.

The Greens defeated Reform UK on 28.7 per cent and Labour on 25.4 per cent. The party’s first North of England MP arrived following a campaign aimed at demographics outside the party’s traditional base, rather than relying on standard community campaigning. The administrative bill came due a few weeks later. On 10 April 2026, Polanski admitted on the record that vetting local election candidates had become a ‘real challenge’.

Byline Times confirmed that the party has no nationally binding rules on candidate selection or vetting. They rely entirely on decentralised local guidance, leaving the central database blind to who is actually representing them.

The Green Party constitution was written forty years ago for an organisation that peaked at 60,000 to 70,000 members. The architecture was entirely analogue.

The failure sequence is highly visible in the documents. A delayed election met a backlogged Disciplinary Committee. A reported directive from the Internal Returning Officer restricted the release of membership data. A contained ballot went ahead, followed by an SOC audit that exposed a lack of reliable records. Then the second wave hit, leading directly to a public admission of vetting failure.

Sources

Sources include: internal documents and leaked data cited by ‘Novara Media’ (June 2025); the 22 September 2025 Standing Orders Committee ruling published via the ‘Greens in Exile’ blog; electoral result datasets from the 2025 leadership election and the 2026 Gorton and Denton by-election; press coverage from ‘The Guardian’ (October 2025) and ‘Byline Times’ (April 2026) regarding local branch capacity and candidate vetting; and analysis from the ‘Green European Journal’.