The information watchdog has been asked to investigate the alleged use of robocalls by Len McCluskey’s campaign team in the increasingly fractious contest to head the union Unite.
Union members say they have received calls in which a recording of McCluskey claims Unite is being subjected to a takeover by a rightwing faction and asks for their support.
The complainants say they had not given permission for their telephone numbers to be used in this way. If the Information Commissioner’s Office finds a breach of privacy laws it could result in a five-figure fine.
The ICO is already examining claims that McCluskey’s opponent Gerard Coyne’s team used mayoral campaign and Labour party data to canvass potential supporters.
Unite, which has 1.4 million members, gives Labour £1.5m a year and many of the party’s MPs see the election for general secretary as a proxy battle for control of the Labour movement.
McCluskey is Jeremy Corbyn’s most influential backer while Coyne is supported by a large number of the parliamentary party including the deputy leader, Tom Watson. Voting closes on 19 April.
One ICO complainant, a branch secretary from the East Midlands, said he was surprised to receive an automated call from McCluskey last week because he had never registered himself as a supporter.
“The basic message was: ‘Hi, this is Len McCluskey. The right is trying to take over the Labour party.’ It then went on about Gerard Coyne. I got the impression that it wasn’t really the union they were concerned about, it was the Labour party,” he said.
“At no stage have I shared any information about the branch with Len’s campaign. So I don’t know how they got hold of my telephone number. That’s why I complained to the ICO.”
The ICO considers robocalling in certain circumstances to be harassment. Regulation 19 of the Privacy and Electronic Communications Regulations 2003 states that automated marketing calls are illegal unless the person receiving the call has specifically consented to receiving that type of call from that specific caller.
Any fine is directly proportionate to the size of the organisation. If there has been a breach of the rules, the ICO could make a judgment on whether this was the fault of McCluskey’s campaign or the union.
An ICO spokesperson said: “We have received a complaint about the alleged use of automated calls by the Len McCluskey leadership campaign. This will be included in our enquiries about marketing and the use of personal data in both the Coyne and McCluskey campaigns as part of the Unite leadership election.”
Some union officials claim the phone numbers used by the McCluskey campaign must have come from the union. A spokesperson for Unite has denied this. “Unite has not supplied any campaign with any member data,” she said.
In March the ICO fined David Lammy £5,000 for authorising 35,000 calls over two days during his campaign for the Labour nomination for London mayor.
The ICO is already investigating claims that a call centre used by Labour’s West Midlands mayoral candidate Siôn Simon has been used to contact party members to see if they will support Coyne, and is looking into whether Coyne’s campaign has accessed Labour party data.
Tom George, 72, a Labour party member, complained after receiving an email from Coyne last month asking for his support. “I said I have never been a member of the union. I want to know how he got my details. He is acting like a bilge rat, running around in the dark looking for support,” George said.
A spokeswoman for McCluskey’s campaign denied any breach of the rules. “Contact has only been made when the necessary permissions have been given, and branch processes have been upheld at all times,” she said.
Coyne’s campaign has also denied breaching the rules.
McCluskey gathered significantly more support during the nominations process, gaining the backing of 1,185 branches, five times more than Coyne.
Coyne’s team hope to bring about a higher-than-usual turnout in the election. The low turnout in internal elections – 15.2% voted in the 2013 general secretary contest – is seen as giving disproportionate influence to the union’s radical activists, who would be more likely to back McCluskey.
The campaign has become increasingly fractious, with claims from McCluskey that Coyne is being directed by a “cabal” of West Midland MPs.
Coyne has called for a cleanup of Unite’s finances after the disclosure that the union contributed more than £400,000 towards the purchase of a £700,000 flat in central London for McCluskey.