Two and a half years on from the EU referendum, the result is still being discussed and debated. Arguably more important though is another story: whether the rules of the game are bust.

The weekend saw fiery battles over the £8m given by businessman Arron Banks to his Leave.EU campaign (Banks insists the money came from UK-based business). He has been referred to the National Crime Agency after the Electoral Commission raised concerns over the true source of the cash.

That investigation however concerns less than £3m. £5 million of this money was donated outside of the regulated period of the EU referendum – and therefore Banks is under no obligation to account for its source. That money could have come from basically anywhere, and anyone – and voters would have no recourse.

Dark money is bigger than Brexit.

Millions of pounds could be changing hands right now – a spending arms race – as various groups push for a second vote on Brexit, and others seek to resist it.

If this money is being spent in a bid to influence people’s view on Brexit or the European Union – or anything else they may in future be asked to vote on – it’s fair to say we have a right to know the source of this money.

Without transparency or up-to-date rules, those with the deepest pockets can exert the most influence, swaying the debate in their favour.

It is just one reason why regulated campaign periods should be extended to the point at which a vote is announced. Otherwise, as the Electoral Commission have highlighted, the period between a vote being announced and the vote taking place is a spending free-for-all: a rush to dodge the rules.

‘Dark money’ is not the only issue here. The Cambridge Analytica revelations earlier this year showed how personal data is being used to target voters in ways which are often deceptive and unapproved.

The law remains unchanged: political adverts can still be published online without any information regarding their source or who funded it. That prevents voters from being able to assess the validity of their messages. And while Facebook have opened up under pressure, we can’t leave this at the whim of tech giants.

There are measures which can be taken. Digital ‘imprints’ on online ads are one obvious vital change, stating both the origin and funder of adverts.

A register of adverts could also be created so people can track all political adverts on a particular subject, not just the ones which have targeted them.

And we need a review of campaign rules across the board, to bring the analogue-age rules kicking and screaming into the 21st century.

Whether it’s dark money or data manipulation, trust in democracy requires transparency.

We are finding that so much of the Brexit referendum took place under the cover of darkness. And there will come a time when Brexit is done, but elections will go on. As things stand, we risk slipping into democracy-in-name only.

This is especially pertinent when our election results are defined by tiny swings: the Conservatives would have won a majority if just 0.0016% of voters had chosen differently last year.

Not many people need to be swayed for there to be a different Prime Minister – and unscrupulous organisations and states know it.

While the Arron Banks story will fade away, the issues it raises will not. Let’s sort out our broken campaign rules while we still can.