Facebook website. After much prodding and reporting the Information Commissioner's Office today said it was launching an investigation into how data analytics, especially from platforms like Facebook, is being used for political purposes.

The ICO's investigation could have huge consequences for how political parties conduct campaigning online. Guidelines so far have been so sparse that many see it as 'free for all' and money has poured into data analytics to influence elections.

The ‘formal investigation’, as the ICO calls it, will also look at the privacy implications that have arisen from companies spending millions of pounds to learn and understand the political habits of voters.

In a blog-post published today the UK Information Commissioner Elizabeth Denham wrote: “This will involve deepening our current activity to explore practices deployed during the UK’s EU Referendum campaign but potentially also in other campaigns. Given the transnational nature of data the investigation will involve exploring how companies operating internationally deploy such practices with impact or handling of data in the UK.”

More interestingly she admitted the ICO will have to work with third parties for the investigation.

The investigation is certainly a big deal. Prof. Helen Margetts of the Oxford Internet Institute told Sky News recently that election regulations online were “totally non-transparent”.

She added: “On a social media platform it's a secret world that's unique to a small group of people and we just don't know what those advertisements are saying or how they are targeting people or about their accuracy. And I think that's what's different and that's what's worrying."

It’s likely the ICO investigation was prompted by the excellent work Carole Cadwalladr has been doing at the Observer in trying to uncover how American billionaires had poured a huge amount of money to influence the Brexit outcome.

Ms Cadwalladr told openDemocracy UK today: “It's great that the ICO is taking the subject seriously and a wider assessment of the use of data for political purposes is desperately needed. But, we also must get to the bottom of what happened during the EU referendum. Multiple British laws appear to have been broken. Yet there's no way of holding the campaigns to account.”

She added: “It's profoundly troubling to me that Britain is plunging ahead with another election with so many questions hanging over the legitimacy of the referendum result. I really don't think this is about Leave or Remain, it's about the law. And our ability to enforce our laws.”

She added that the ICO had been much more responsive than the Electoral Commission on the issue.

The Information Commissioner’s Office said they will present their report later this year.