With so much focus during the past two years on Labour’s approach to dealing with antisemitism, questions have regularly been asked about how other parties handle complaints against members.

Rather unexpectedly, I have just had first-hand experience of a protracted case with the Green Party.

In July I discovered that a Jewish anti-Zionist Green Party activist was sending foul and abusive messages on social media — and had been doing so for many months.

Some of the tweets were targeted at Jewish groups, including dozens to the Jewish Labour Movement. One message carried the accusation: “You’re no Jewish movement: you’re just Zios.”

Another message, in which the activist tagged me , invoked the party itself, stating: “Greens know the difference between real antisemitism & the Zio definition of it: criticism of Israel.”

The activist has stood for election as a Green candidate in the past and has just shy of 1,000 followers on Twitter.

Among his more recent efforts was one after Labour’s conference in September about its general secretary, which read: “Iain McNichol [sic] Sucks up to the Zios. He suspends members, including Jews, who Zios complain about.”

After the flurry of abuse in the summer I tweeted the party hierarchy, including joint leaders Jonathan Bartley, Caroline Lucas MP and Jenny Jones to see what would be done. Only Baroness Jones replied, suggesting I write to the party to check its policy on such matters.

I did so.

After a fortnight of repeated reminders, the party replied to say the complaint was being forwarded to its disciplinary committee.

Emailing colleagues, the party chair wrote: “I just want to reassure Marcus that equality and freedom from discrimination and harassment are at the heart of the Green Party and our policies.”

I was directed to the Greens’ “core values” and “specific provision against antisemitism”.

The party says it is committed to taking action against Jew-hate. Further details of what exactly would be done about it, however, were not evident.

By mid-September, having heard nothing more, I chased the party chair. A month later the party’s governance administrator apologised for the delay and sent me his findings.

“This matter has been considered by a number of senior volunteers in our disciplinary process,” he wrote. “It has been concluded that the word ‘Zio’ is problematic.”

The activist had been written to and “advised of the problems around the word”. The tweets were sent in a personal capacity, he added, and not in a “Green Party capacity”. How reassuring.

Was there any deeper assessment of the abuse than it being “problematic”, I inquired, and what further action might be taken beyond a letter offering advice?

But the governance gentleman ended the correspondence by pointing out: “I am not sure what more I can usefully add.”

The Greens have a policy passed nearly a decade ago condemning Jew-hate and warning members to avoid it. But there are no specified details on the potential consequences for repeated abuse of Jews.

Discredited as she and her racism report may be, Shami Chakrabarti last year provided a reasonable assessment of how “Zionist” and “Zio” have been used “personally, abusively or as a euphemism for ‘Jew’”.

Her recommendations included removing the word “Zio” from Labour discourse, and increasing sanctions against those who use the term.

In approaching the Greens I had hoped to find a party which had learnt from Labour’s trauma. I also wanted the abuser dealt with appropriately.

But there is only one conclusion. Warm words and jolly slogans mean nothing unless, when antisemitic abuse trundles onto the scene, it is crushed — fully and forcefully.

It is duplicitous for the Green Party to claim “freedom from discrimination and harassment” are “at the heart” of its policies, when the evidence suggests the opposite.