The Commission announced that it had fined Vote Leave £61,000 and referred the pro-Brexit campaign group to the police over breaches of electoral law.
The results of the investigation into spending limits by groups involved in the 2016 EU Referendum campaign were published on Tuesday.
Vote Leave and the opposing Remain campaign, Britain Stronger in Europe, were given statutory spending limits of £7m each for the official campaign period.
But the Commission said Vote Leave sidestepped those limits by channelling money through pro-Brexit youth group BeLeave and fined its founder, Darren Grimes, £20,000. It also referred Grimes and Vote leave official David Halsall to the police.
In a statement, Bob Posner, the Commission’s legal counsel, said it had uncovered "substantial evidence" that Vote Leave and BeLeave were working together, did not declare their relationship and did not stick to legal spending limits, before launching an extraordinary attack on Vote Leave’s obstruction of its investigation.
He said: "Vote Leave has resisted our investigation from the start, including contesting our right as the statutory regulator to open the investigation. It has refused to cooperate, refused our requests to put forward a representative for interview, and forced us to use our legal powers to compel it to provide evidence."
We open investigations where the evidence justifies it, irrespective of the political views of the party or campaigner concerned.Electoral Commiassion spokesperson
The Commission’s report detailed how it had asked Vote Leave to provide documents relevant to its investigation, and for a representative to submit themselves for an interview.
It said Vote Leave repeatedly objected to the investigation being opened at all and even threatened to apply for a judicial review into the decision, although it later dropped the idea.
The Commission also said that Vote Leave repeatedly failed to agree on dates for an interview, in direct contrast to comments made in reaction to the investigation by former Vote Leave chief Matthew Elliot, in an interview with BBC political editor Laura Kuenssberg.
He said: "We’ve offered to go into interviews, both at a board level and also at a staff level, but they haven’t accepted any interviews from our side."
A spokesman for Vote Leave accused the Commission of launching a politically motivated attack on it with its investigation.
He said: "Vote Leave has provided evidence to the Electoral Commission proving there was no wrongdoing. And yet despite clear evidence of wrongdoing by the Remain campaign, the Commission has chosen to ignore this and refused to launch an investigation. All this suggests that the supposedly impartial Commission is motivated by a political agenda rather than uncovering the facts."
However, the Commission rejected the suggestion that its report was politically motivated and said that it had carried out 38 investigations between June 2016 and April 2018, 14 of which were into Remain campaigners.
A spokesperson told PRWeek: "We open investigations where the evidence justifies it, irrespective of the political views of the party or campaigner concerned. We publish all investigation outcomes online, including details of any fines."
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