The police force is a giant in data collection, embracing an ever increasing number of sources from driving licences to DNA to Transport for London’s Oyster card payment system and its numberplate identification collected as part of the congestion charge.

The diversity of sources highlights the debate about information sharing that Richard Thomas, the information commissioner, sparks again on Monday. As companies and public authorities collect an increasing amount of our personal data, so concerns are increasing about the accuracy of that data and the way they are used and shared.