The era of click-to-consent data sharing is coming to a close. Until now, users of Facebook and other social networks were dimly aware of the collective value of personal information. There was a tacit contract: in exchange for useful services, the technology companies would suck up the data and use it to sell advertising. As long as the privilege was not abused, users appeared happy to go along with it.

Yet this minimum standard has not been met. The Cambridge Analytica scandal is an example of why trust in Big Tech is collapsing. Users tend to gloss over privacy agreements contained in dense terms and conditions, so companies like Facebook took advantage for commercial gain. The public has realised the degree to which data are being used and abused — particularly for political campaigning.

The backlash is under way and technology businesses cannot counter it alone. Changing culture and the law is needed if users are to regain trust in sharing their data. The first step is tougher law enforcement. When businesses break laws, suitable penalties should ensue. The same is true for data breaches: they must be fully disclosed. Much like an environmental disaster, data spills need cleaning up.