Almost 1400 women are preparing to launch legal action against their trade unions over the way officials dealt with historic equal pay disputes within Scotland’s councils.

The workers, some of whom claim to have lost out on tens of thousands of pounds, are lodging claims against Unison, Unite and GMB under a new class action process introduced in Scotland earlier this year.

The claims – 800 of which are due to be lodged at the Court of Session within weeks - are being brought by claims management firm DM Legal Claims, who are pursuing arguments of negligence, breach of contract and breach of fiduciary duty on behalf of the women.

Leading advocate Robert Milligan QC has been instructed in the case, which centres on allegations that union officials failed to timeously pursue equal pay claims on behalf of members and deterred some women from pursuing cases against local authorities.

The Herald has heard from three former home carers who are all taking Unison to court after being told for years that they had no claim. Two of the women went with independent solicitors to pursue a claim and received more than £30,000, while one – who worked part-time – followed the advice of the union and received just £4000.

GMB Scotland said it would respond to the claims if they are lodged in court, Unite declined to comment and Unison failed to respond to The Herald’s request for comment.

Alison Martin, of DM Legal, said years of delay in lodging claims meant that many union members received a much smaller payout than colleagues who pursued their case earlier using independent firms.

Ms Martin, who is based in North Lanarkshire, said: “This all began with workers from North and South Lanarkshire getting in touch, but then Glasgow happened and we started to hear from women there, too.

“We began to realise that it was a much bigger problem than we had anticipated and it has just grown and grown since then. We now have clients from Falkirk, Fife, East Ayrshire and Aberdeen.

“Our QC, Robert Milligan, wants to steam ahead, especially now with the new litigation proceedings in place, so we plan to lodge the Lanarkshire cases within weeks.”

She added: “There’s a high level of trust between workers and their unions, especially in Lanarkshire, it’s a big union area. So when people were told they didn’t have a claim, they didn’t claim.

“Their members were paying them to look after their rights and they didn’t.”

The equal pay issue dates back to the late 90s and early 2000s when workers in female dominated jobs were being paid less than those in male dominated jobs at the same skill level.

Solicitors Fox and Partners, Stefan Cross QC and Action 4 Equality Scotland began to notify workers of their right to make a claim for equal pay and started lodging cases around 2005.

Three former workers with South Lanarkshire Council told The Herald that, around this time, a Unison official continually refused to speak about equal pay at union meetings and told them they were “on to plums”.

They also claim they were warned people might lose their jobs if they pursued it.

Anne Robin, Evelyn Conroy and Dorothy McLean worked together as home carers and were shop stewards for Unison.

They found out about a possible equal pay claim from other workers who had been in touch with independent solicitors.

Ms Robin, 66, from Cambuslang, and Ms Conroy, 67, from Burnbank, signed up with the independent group, but Ms McLean, 66, of Rutherglen, followed the union’s advice.

Ms Conroy, who received a settlement of just under £33,000, told of a union meeting in January 2005 when lots of workers were talking about equal pay.

She said: “At the end of the meeting we approached [a union official] about it. He said ‘uch, away you go. Where are you getting this information from? This isn’t true, there’s no equal pay claim.’

“One of the women’s husband was a binman and she said ‘he’s the same as us but he’s getting more money’. He said ‘but these men are skilled’.

“I was fuming. I walked away and thought ‘right stuff you’ and I signed up elsewhere after that.

“For a long time after that, the union were still saying we weren’t entitled to it. We were told ‘you all think you’re getting thousands of pounds but you’re on to plums.’”

Ms Robin, who received almost £35,000, added: “At union meetings, they used to say at the start ‘don’t mention equal pay, we’re not talking about that’.

“I was delighted with what I got, but I’m devastated for my colleagues who went with the union.

“We trusted them and they let us down.”

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Ms Mclean, who worked 20 hours per week compared to the other women’s 35 hours, received £4000.

She, too, said she attended union meetings where she was told by Unison that there was no equal pay claim.

“Once Fox and Cross had won, we brought it up again,” she said. “And [a union official] said the union was going to take up our claim against the council.

“At first, when I got my settlement, I didn’t know what anyone else had received because we were all sworn to secrecy. But then it started coming out and I just felt ‘well, it’s my own fault for going with the union’.

“I couldn’t believe it. I believed what they told me. I felt betrayed.”

Ms Robin and Ms Conroy are pursuing claims for the fee they paid to the independent firm who represented them, while Ms McLean is suing for what she believes she should have received.

Figures from South Lanarkshire show that Fox and Cross represented around 3000 claimants and their payouts totalled £70 million. A later settlement to a further 3000 claimants – including 1000 represented by Unison – amounted to between £10m and £12m.

In DM Legal’s cases, the majority of the claims are against Unison, with around 300 against GMB and less than 50 against Unite.

A spokesman for GMB Scotland said: “DM Legal have been threatening to take legal action against trade unions for the last five years. They’ve taken tens of thousands in fees from low paid women but have never raised a claim. If any claim is ever lodged, GMB will respond in the appropriate forum.”

DM Legal charge a £100 upfront fee and 20% of any settlement.