Sam Tarry, Angela Rayner’s former partner, claims online voting system has been used to disadvantage Left-wing candidates

The Labour Party is facing legal action from Angela Rayner’s former partner over alleged “voter fraud”.

Lawyers acting for Sam Tarry, the MP for Ilford South, have written to the party over claims that an online voting system has been used to disadvantage Left-wing candidates.

Mr Tarry, whose relationship with Labour’s deputy leader ended last year, claims the Anonyvoter system was used to harm his unsuccessful attempt to be re-selected for the general election.

Anonyvoter is a software for holding online votes that is widely used by local Labour Party branches to decide who will be their candidate for the next election.

Mr Tarry lost to Jas Athwal in a selection vote in October 2022 and has been disputing the result since.

He is now considering issuing legal proceedings to force Labour to publish the Anonyvoter records from his selection or even to get an injunction to block Mr Athwal from being the official Ilford South candidate.

Trade unions are helping Mr Tarry raise tens of thousands of pounds, which will help fund legal action if an agreement with the party is not reached.

Meanwhile, a second Labour MP, Beth Winter, who represents Cynon Valley, has been exchanging legal letters with the party over how Anonyvoter was used in her selection race.

Ms Winter sought to become the candidate in a newly created Welsh seat last summer, but lost. Her lawyers wrote to the party raising concerns about the use of the Anonyvoter system both before and after the result.

This week, she has written to senior figures in Welsh Labour widening her complaint beyond online voting and demanding an investigation.

Vote breakdowns seen by The Telegraph show that both candidates did better than their rivals among the voters who took part either in person or by post, but worse among those who cast their ballot on Anonyvoter. Such records are not made public.

Mr Tarry and Ms Winter are both members of the Socialist Campaign Group, the most prominent Left-wing group in the Commons, which includes Jeremy Corbyn.

Since becoming Labour leader, Sir Keir Starmer has widely been seen to have sidelined Left-wing figures. His party is now facing allegations that information generated by the Anonyvoter system is being used at times to help get moderates selected as election candidates.

In one selection, a moderate candidate won just 10 per cent of the in-person vote but 62 per cent of the Anonyvoter online vote, according to a breakdown shared by local party figures.

There is no suggestion the Anonyvoter system is inherently flawed or faulty, but the lack of transparency has raised concerns that it is open to abuse.

Regional Labour figures running the online votes are able to see who has voted, a piece of information that would be critical to campaigns trying to turn out supporters in tight races.

Independent tellers are not usually given access to monitor the Anonyvoter system during the votes, meaning there is no outside oversight of the live online voting process.

The news comes as the Metropolitan Police this week confirmed its cyber team was investigating “computer misuse” in the selection of a Labour candidate in Croydon East after claims of vote-rigging.

Mr Tarry and Ms Winter are both now calling for use of Anonyvoter in picking candidates to be suspended and for Civica, an online vote company used by other political parties, to be used instead. ‘Labour deserves better, as do the British people’

In a statement to The Telegraph, Mr Tarry said: “The Labour Party hierarchy has failed to resolve this matter, despite me submitting a formal appeal over a year ago.

“I am extremely reluctant to seek legal redress, as we should be focusing all our efforts and resources on the general election, but it is impossible for this situation to stand.

“Labour Party and Labour movement figures at the very highest levels have seen the evidence, and are backing me in seeking a fair resolution. However, what’s gone on in Ilford South, and allegedly in other selections too, is unlike anything I have seen in 20 years in the Labour Party, in elected positions under four party leaders.

“Labour deserves better, as do the British people, who need to be able to trust our party. As a party that hopes to form the next government, and has my full support to do so, we should be operating at the highest level of electoral and ethical integrity.

“The Labour Party owes it to its members and the voters to resolve this democratic outrage before it becomes a full-blown crisis that will harm our electoral performance. The use of Anonyvoter must be stopped immediately.”

Ms Winter said in her statement: “The ongoing controversy around Anonyvoter voting software understandably leads to a lack of trust and confidence in Labour Party procedures. Continued use of the software risks bringing the party into disrepute.

“In order to restore some trust in the party, there must be an independent review of the use of Anonyvoter in internal selection campaigns, including the selection process in Merthyr Tydfil and Upper Cynon.

“In addition, Labour should end its use of Anonyvoter and commission a trusted independent balloting administrator, whose ballots stand up to scrutiny, such as Civica (formerly Electoral Reform Services) – as the trades unions do – to conduct its internal ballots including parliamentary selections, in future.”

It is understood that Labour Party figures have disputed whether the two MPs have the evidence to back up their claims. Critics have said their defeats could be the real motivation for the complaints.

A Labour spokesman said: “We have full confidence in the integrity of both selection processes and the use of Anonyvoter.”

The Anonyvoter website states that its software allows organisations to “conduct secret ballots remotely where voters want to be sure their votes are anonymous”.

Labour’s widespread use of the system started during the pandemic, with the software being used for votes on issues at local branch meetings as well as for selections.

There are concerns about how it is used by those who run the votes for Labour party candidates, often regional party officials.

The system works by inviting Labour members to take part in a vote via email. The vote runs for a set period of time. Who won how many votes is announced at the selection meeting.

One concern raised by Left-wing Labour figures is that, throughout the process, whoever is running the vote can see which members have voted and which have not.

Such information, if shared with a campaign team, could be significant. As selection votes often only involve a few hundred people voting and tight margins, they could use the information to attempt to engage their own supporters, potentially impacting the result.

Another concern is that the system allows for new members to be added while the vote is ongoing. It is understood that data showing when voters were added is not routinely handed over to candidates at the counts.

A third area of concern is that members who do not receive the email are able to generate a special code to vote, which can be communicated to them over the phone if needed. In theory, codes can be generated and even cast by those running the votes. Again, any data about how many codes have been generated and for whom are not routinely published.

At the heart of the concerns is a lack of observation of the online votes as they take place. Independent “tellers”, whose job involves observing a voting process to make sure it is run properly, are not usually given access into the system to monitor the vote.

This is different for in-person votes, when members of a campaign’s team are often present, and postal votes, which are often opened and counted on tables in front of campaign teams.

One Left-wing Labour source said: “It is a black box. There aren’t really checks and balances. There is an easy way of doing this, which is independent tellers. But those suggestions have been rebuffed. The only check and balance we have is the supposed integrity of the regional staff.” Records of those present must be relied on

To select candidates for a general election, each local Labour branch decides whether to do in-person voting, postal voting, online voting with Anonyvoter, or a combination of all three.

A breakdown of the results of the candidate selection vote is not published but is often read out at the count, meaning the records of those present must be relied on for the figures.

Mr Tarry, a former political officer at the TSSA trade union, has been the MP for Ilford South since 2019. In the summer of 2022 he faced a trigger ballot, a Labour Party mechanism that lets local parties force a re-selection vote, losing the subsequent vote that October.

Mr Athwal, the Redbridge council leader, won the selection. He had been endorsed by Wes Streeting, Labour’s shadow health secretary and one of the party’s leading moderate figures.

Mr Tarry is understood to have won 57 per cent of the in-person votes at the selection but just 35 per cent of the Anonyvoter votes, plus a small number of postal votes. Mr Athwal won 43 per cent of the in-person votes but 65 per cent of the Anonyvoter and postal vote.

The vote breakdown was provided by Mr Tarry’s team. No record is published by the party. Labour and Mr Athwal did not dispute the accuracy when approached for comment.

In late 2022 and early last year, the law firm Carter Ruck, acting on behalf of Mr Tarry, exchanged letters with senior Labour figures requesting a formal appeal and seeking disclosure of the Anonyvoter data.

A year on, the dispute has not been resolved. A further letter was sent to Labour earlier this month, addressed to James Asser, the chairman of the party’s National Executive Committee. David Evans, who as general secretary is Labour’s most senior official, was copied-in.

The lawyers noted that Mr Tarry had sought the disclosure of records generated by Anonyvoter about how each vote was cast, the date and time each ballot was issued, where new codes generated were sent and how those votes were cast.

It read: “Mr Tarry believes there is evidence of voter fraud pertaining to the use of the Anonyvoter system, and specifically, that votes were improperly generated using Anonyvoter in a manner that was unfavourable to our client and favourable to his opponent.”

Elsewhere, the letter said Mr Tarry had been “denied the opportunity to scrutinise the electronic voting record” despite the “obvious seriousness” of the concerns raised. It made clear information on how individuals voted was not wanted, only detail on time and method of the votes. An ‘isolated incident’

One complaint made in writing by Mr Tarry during the trigger ballot process in the summer of 2022 regarded a Labour member being alerted that they had voted via Anonyvoter to force a reselection. However, the Labour member in question was abroad in Italy at the time and had not taken part in the vote.

It is understood the Labour Party investigated the claim at the time and accepted an error had occurred, but concluded that it was an “isolated incident”.

The complaints by Ms Winter, the MP for Cynon Valley since 2019, regard a selection for Merthyr Tydfil and Upper Cynon, a newly-created seat as part of the boundary review.

Ms Winter competed against Gerald Jones, the Labour MP for Merthyr Tydfil and Rhymney, who was made shadow Scotland minister by Sir Keir in September.

She won 56 per cent of the postal votes but 47 per cent of the Anonyvoter votes, according to a breakdown recorded by her team. There were no in-person votes.

Mr Jones won 43 per cent of the postal votes – there was one abstention – but 53 per cent of the Anonyvoter votes, meaning he will be the candidate for the new seat.

Before and after the June 2023 selection, Ms Winter’s lawyers Howe+Co sent letters to senior figures in both the UK Labour Party and Welsh Labour raising concerns about the process.

A letter sent to Jo McIntyre, the general secretary of Welsh Labour, before the selection raised concerns about using online voting, saying: “As you are aware from previous trigger ballots and selections, there is serious disquiet among some parliamentarians and party members that online processes have produced and will continue to produce undemocratic results which lack fairness and transparency.”

Ms Winter demanded a detailed breakdown of the Anonyvoter data, including how many codes allowing people to vote directly were generated.

The Welsh Labour Party declined to publish the detail Ms Winter requested, citing data protection rules.

This week, Ms Winter raised new concerns in a letter she sent on Wednesday to Ms McIntyre and Vaughan Gething, the new Welsh Labour leader.

The claims were not related to Anonyvoter, unlike the correspondence sent by her lawyers last year, but the new letter underscores that she is continuing to dispute the selection.

Mr Jones and Welsh Labour were approached about Ms Winter’s claims, but neither issued a comment. Anonyvoter was also approached about claims that its software is being misused to benefit moderate candidates. The company did not issue a comment. Momentum urges investigation

Momentum, the Left-wing activist group that championed Mr Corbyn’s leadership, called for an “immediate, comprehensive and independent investigation”.

A Momentum spokesman said: “We need an independent, KC-led investigation into Labour’s selections, and the replacement of Anonyvoter with an independent system such as Civica to ensure the integrity of the party’s processes and confidence in their outcomes”.

The allegations emerge amid a wider tussle between Labour’s Left-wing faction and its moderates, now effectively led by Sir Keir, for the control of the party, that has raged for years.

Centrists once accused Mr Corbyn, the Left-wing Labour leader between 2015 and 2020, and his allies of trying to sideline moderates and triggering deselection votes during his tenure.

Now under Sir Keir, who took over from Mr Corbyn in April 2022, some of the party’s most prominent Left-wing MPs face being forced out of Parliament at the next general election.

Mr Corbyn was stripped of the Labour whip after refusing to accept findings of an anti-Semitism report, meaning he cannot stand for the party in his Islington North seat.

Diane Abbott, who was Mr Corbyn’s shadow home secretary and the first ever female black MP, lost the Labour whip 11 months ago over a comment about differing forms of racism for which she has apologised. The party disciplinary process is yet to be completed.

Currently, Ms Abbott cannot stand for Labour for re-election as the MP for Hackney North and Stoke Newington, a seat she has represented since 1987.

Mr Tarry and Ms Winter are yet to be selected for other seats after they lost their selections. If nothing changes, both are likely to no longer be MPs this time next year.