The new revelations about Cambridge Analytica and its alleged use of data from Facebook reinforces concerns I have been writing about for some time about the scope for social media interference with our minds and our democracies.

The legal and regulatory reaction has focused on data protection and the defences of both Facebook and Cambridge Analytica in front of Parliament and to the media turn on details of regulatory compliance.  But a bigger question is whether or not our regulatory framework is fit for purpose given the potential uses of data in the modern world.

Big data offers insights and possibilities for manipulation that go beyond privacy.  They touch directly on the right to freedom of thought - a right that is protected absolutely in human rights law.  Quite simply, if an activity interferes with our freedom of thought, it should not be allowed and States have an obligation to protect us from it.  But the current legal framework is not sufficient.

Liberal democracy rests on the right to freedom of thought and the assumption that people are able to think for themselves.  But the way that technology has developed to collect our thoughts and emotions and turn them back on us calls that fundamental assumption into question.  Whatever the reality turns out to be of Cambridge Analytica and similar companies' involvement in our democratic processes and the rise of populism, we can no longer ignore the potential for the techniques they use to undermine the legitimacy of our whole political process.   It is time to act.