The former deputy prime minister Sir Oliver Dowden was questioned by the Gambling Commission in the early summer over the alleged bets placed on the general election date by some Conservatives.

The Commission is not investigating Sir Oliver, and he himself didn’t place any bets on the election.

The revelations about betting – many revealed by the BBC – rocked the Tory campaign for days on end.

In a leak on the opening day of the Conservative conference, first reported by Sky News, it was revealed Sir Oliver was among those the betting regulator spoke to as part of its inquiries.

It isn’t surprising the Gambling Commission would have wanted to speak to the former deputy prime minister, given the seniority of his position at the time within the government and the Conservative Party.

I understand Sir Oliver’s conversation with them took place before the general election. At the same time, Rishi Sunak’s former chief of staff Liam, now Lord Booth-Smith, spoke to them too.

The leak, about an interview that took place around three months ago, appears designed to damage the Conservative Party as its members gather in Birmingham for their annual conference.

The Tories are picking over their colossal election defeat and an election campaign seen privately by many in the party as a mess – not least because of the torrent of stories about betting.

At least four people are being looked into by the commission in relation to the alleged bets. The Metropolitan Police ended its investigation, after it said the alleged offences did not meet the “high bar” to prove misconduct in public office.

The Gambling Commission said it would not comment on the specifics of an ongoing investigation.