PERSONAL data of voters across south east Dorset has been mistakenly sent to the wrong home due to a blunder with the delivery of postal votes.

In a number of cases, ballots for multiple people with no connection to each other have been delivered to one address by the printer contracted by BCP Council.

The council is responsible for overseeing the Bournemouth East, Bournemouth West, Christchurch, Mid Dorset and North Poole and Poole constituencies for the December 12 general election.

It has now launched an investigation into the issue. A spokesman said it had received 32 reports as of yesterday evening (November 28) but had “no idea” of its true scale.

A source, who asked not to be identified, told the Local Democracy Reporting Service that between 4,000 and 6,000 people may have been affected.

“This is a huge and very serious data protection breach,” they said.

“Postal ballots are often requested by people who know they are going to be away over the election.

“This is one of the most important elections we have had and some of these people may now not be able to take part – it’s not going to be a fair vote.”

They said the council had been urged to make the issue public yesterday but had decided to keep it under wraps.

The council spokesman said they had planned to do so after all postal ballots had been sent out.

“With 55,000 registered postal voters in the BCP Council area there is always the potential for issues to arise, especially when dealing with a snap election", they said. 

“In this case it appears a handful of postal voting packs sent out enclose not only their form but also those belonging to an additional elector.

“The numbers appear small and as these have been reported they are formally recorded and a member of Elections team has personally visited to collect the form, and redelivered a postal voting pack to the correct elector.

“We are in constant communication  with our printing supplier about how this has happened and apologise to anyone who has been affected.

“We would also like to reassure everyone that due to the high number of failsafe checks and measures in place with the postal voting system, we are confident that the risk of anyone casting more than one vote is fully mitigated.”

Errors were also made on some ballot papers which had birth years pre-filled with the digits ’20…’ on forms delivered to people born before the turn of the millennium.

The council also blamed its printers for delays issuing postal ballots ahead of the local elections in May.

A spokesman for the Electoral Commission said it was aware of the issue and was working with the council to “understand how the error happened”.