THE Scottish Labour leadership race was last night described as a “farce” after a senior Scottish Socialist activist became the latest of the party’s opponents to be registered to vote.

Sandra Webster, a former national co-spokesperson of the SSP, appeared on a list of names of affiliated supporters presented to the Paisley constituency labour party for them to check.

Webster, who stood against Labour in the local council elections in May and was SSP co-spokesperson from 2011 to 2015, was furious when told she was among the names of prospective voters being circulated.

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She said she wanted her name to be taken off the list immediately and believed it could have been added after she received a text message from the trade union Unite of which she is a member.

“I am very upset at this. During the independence referendum I spoke all over Scotland campaigning for a Yes vote,” she said.

“I am a member of Unite as I am a socialist. I was sent a text by Unite asking if I wanted to be affiliated and I replied no as it’s nothing to do with me.

“I certainly won’t be voting. I don’t know why my name is on this list and I will be speaking to Unite about this.”

The development comes just days after it emerged a SNP and a Green councillor had also been listed as affiliated supporters.

The bitter battle between left-winger Richard Leonard and moderate Anas Sarwar has been dogged by complaints over the controversial procedure for signing up new supporters.

Under Labour rules, those wishing to vote can join as a full member, sign up as a registered supporter or become a supporter of an attached trade union. But there are fears the decision to allow new members to join until October 9 has opened the system up to abuse. Any affiliated or registered supporter is expected to support the aims and values of the Labour Party. Members of rival parties are not eligible to vote.

Sarwar supporters have previously raised concerns after Unite — who are backing Leonard — sent a mass text message to members urging them to register and vote in the contest. A verification panel has been set up to ensure all those joining the party are legitimate. Party bosses have yet to complete the process. Voting in the contest opens tomorrow.

“It’s deeply embarrassing that yet another representative from a rival political party appears to have slipped through the net,” said a Labour source. “This backs up serious concerns already raised that Unite is signing people up without their explicit consent or accepting Labour’s aims and values. Given how many thousands have been added to the list of voters by Unite, you have to wonder how many more non-supporters have votes in this contest.”

A second Labour insider added: “This contest is becoming a farce. Scottish Labour must review its rules — either you are a member of the Labour party and you can vote in the contest or you’re not a member and you can’t.”

Sarwar yesterday unveiled proposals to overhaul income tax rates and bands, describing his plan as “more radical” than the party’s current policy. The blueprint would see those earning less than £28,000 a year pay less income tax than they do today, and less than under Labour’s existing tax plan.

Under his plans, the current 20 per cent basic rate would be split into two new bands, with a 15 per cent rate for earnings above the estimated 2018/19 tax-free personal allowance of £11,800 and up to £18,000. Earnings between £18,001 and £42,385 would be taxed at 23 per cent. The higher rate of tax — currently 40 per cent for earnings above £43,000 up to £150,000 — would be changed to 43 per cent for earnings between £42,386 and £100,000.Sarwar would also introduce a 50 per cent rate for £100,001 and upwards. In response to Webster’s name appearing on the list of affiliated supporters, a spokesman for Sarwar’s campaign said: “We hope the party will fully investigate this.”

A Scottish Labour spokesman said the verification process would be completed by the time the ballot opened and added:”The party has a robust process in place to ensure verification of new members and registered supporters.”

Unite was unable to say how many affiliated supporters had signed up through it.

They said last night: “Our offices are now closed. This makes it impossible to access our membership records. So at this point we cannot make an informed comment on the accuracy of these allegations.”

Labour later responded to say that on background, on checking, this individual was rejected and will not be allowed to vote.