Zack Polanski faces leadership questions after Holborn byelection defeat

Zack Polanski has lost the Holborn and St Pancras byelection to Labour, with the party's candidate Sagal Abdi-Wali securing 45% of the vote. Polanski received 33% of the vote in the north London constituency. The result follows a period of internal party turmoil and a significant drop in Green Party polling.

Falling Polls and Internal Criticism

Since the Green Party's victory in the Gorton and Denton byelection in February, national polling for the party has fallen from highs of 21% to approximately 10-11%. New polling from More in Common indicates Polanski's net approval rating has dropped to -28, positioning him as less popular with voters than Nigel Farage and the least popular major UK party leader. This decline in public standing has been exacerbated by a controversial motion adopted at the Green party conference equating Zionism with racism. Polanski's decision to abstain from this vote, choosing instead to campaign in the Holborn and St Pancras byelection, drew criticism from senior party figures, including former leader Caroline Lucas. Lucas stated that Polanski "should have been there and he should have voted."

Vivien Lichtenstein, leader of the Jewish Greens, called for Polanski to step down, describing his absence from the vote as a "big mistake". However, some within the party, such as the Greens Organise faction, have defended Polanski, arguing that "not all growth and success is linear" and that the party has "reshaped the British political landscape."

Membership Growth and Electoral Gains

Despite the recent challenges, Polanski's leadership, which began in September 2025, has seen the Green Party's membership reportedly quadruple to over 230,000. Under his tenure, the party also achieved its first directly elected mayoralty in Hackney, east London, and secured its first parliamentary seat in the north of England with the Gorton and Denton victory.

Camden councillor Hamza Chowdhury, who was overlooked for the Holborn and St Pancras candidacy in favour of Polanski, described the byelection result as "a huge win for the Green party and the wider movement", pointing to a 13-point swing from Labour.

Future Challenges

Luke Tryl, director of More in Common, noted that Polanski has become a more polarising figure. He suggested that missteps, such as sharing a social media post critical of police following the Golders Green stabbings, have damaged Polanski's popularity with the wider public. James Baggaley from UCL's Policy Lab suggested that rebuilding popularity would require a return to economic messaging and addressing concerns about antisemitism, rather than focusing on internal party disputes.

The path forward for the Green Party and Polanski involves navigating upcoming policy decisions on issues such as North Sea oil drilling and the national budget, while also addressing internal divisions and public perception.