The Labour party is investigating whether any data rules have been broken in its leadership contest after it emerged that party members’ phone numbers were potentially accessible to the Rebecca Long-Bailey campaign and Momentum this weekend.

Officials acted after HuffPost UK discovered that Long-Bailey’s campaign had shared with its volunteers links to Labour’s official phone-banking system, a move that allowed them to, in theory, contact and lobby any of the party’s more than half a million members.

But the party – which appears to have now suspended its phone bank website – was also likely to face criticism itself for failing to adequately protect the data of its rank and file members across the country.

Access to members data – crucial to any campaign in garnering support in the leadership and deputy leader elections – is tightly restricted until after February 14, under rules approved by Labour’s ruling National Executive Committee (NEC) earlier this month.

However, both the Long-Bailey campaign and Momentum worked in tandem this weekend to share with volunteers links to Labour’s own ‘Dialogue’ phone bank system that accesses members in constituencies across the UK.

The shadow business secretary is vying with rivals Keir Starmer, Lisa Nandy and Emily Thornberry in the race to succeed Jeremy Corbyn, with the winner announced on April 4.

The Long-Bailey campaign and Momentum used a renewed version of Momentum’s ‘MyCampaign.com’ app that included WhatsApp and Facebook groups with links to spreadsheets used to mobilise activists in marginal seats in the last election.

The Long-Bailey campaign insisted that there were “no plans” to use the Dialogue system. Sources suggested the anomaly had arisen because old WhatsApp and Facebook groups used during the last election had been included in the new campaign tool. Read more

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