Andrew Fisher has already been challenged over claims that he tweeted for voters to back a Class War candidate in Croydon in the 2015 election rather than the official Labour candidate, Emily Benn.
Benn has formally complained to the party, and the issue has been raised twice at the weekly meeting of Labour MPs – both by the former shadow energy secretary, Caroline Flint, and by the former shadow business secretary, Chuka Umunna.
A piece published by the Alliance for Workers’ Liberty in 2009 alleges that Fisher urged support for the Green party’s Caroline Lucas, who was then a candidate against David Lepper, the former Labour MP for Brighton Pavilion. Lucas went on to win the seat in 2010.
Fisher also sent a “personal statement” as secretary to the Labour Representation Committee (LRC) to the Left Unity Liaison Committee asking them to support socialist Green candidates and socialist Labour candidates.
It is an offence liable to lead to expulsion for a party member to advocate support against an official Labour candidate.
The shadow chancellor, John McDonnell, has dismissed the Class War tweet, saying it was an innocent satire about the idea of anarchists standing for election.
Fisher’s supporters also point out that a Facebook page called Emily Benn for Croydon South published a retweet from someone suggesting Labour members disappointed with the male dominance of Corbyn’s party should consider joining the Women’s Equality party.
It is no secret that Fisher was active in the LRC or that the LRC frequently examined the case for new political formations that might lead to a rival to the Labour party.
But the speed with which Fisher, a vitriolic opponent of New Labour, has risen to one of the most senior positions in the recast Labour party led by Corbyn is striking.
A Labour spokeswoman said: “We do not comment on staffing matters.”
Additional reporting by Rowena Mason
This article was written by Patrick Wintour Political editor, for theguardian.com on Wednesday 28th October 2015 11.55 Europe/Londonguardian.co.uk © Guardian News and Media Limited 2010