There is a sense of despair when it comes to privacy in the digital age. Many of us assume that so much of our electronic information is now compromised – whether by corporations or government agencies – that there is little that can be done about it. Sometimes we try to rationalise this by telling ourselves privacy may no longer matter so much. After all, an upstanding citizen should have nothing to fear from surveillance.

In Dragnet Nation, Julia Angwin, a Pulitzer Prize-winning journalist at The Wall Street Journal, seeks to challenge that defeatism. She argues that surveillance dragnets do matter and can damage lives. For example, she speaks to people who have had their driving licences revoked after facial recognition software flagged them up as looking too similar to another driver. Other cases have involved sufferers of mental illness being horrified to discover that what they thought were private chat forums were being monitored and recorded by drugs companies. And while the individual cases are still relatively isolated, Angwin points to an enormous potential for further harm. She reminds us that the Stasi surveillance networks, which had such a chilling effect on East Germans, were nothing compared to the social mapping now available through services such as Facebook.

Angwin spends a year seeing if she can escape the dragnets. The project is exhausting and mostly futile. She disconnects from 91 data brokers which have collected her information, a costly process that takes months. And at the end of it, another 120 companies, which do not offer an opt-out, still hold her data in their files. She begins using a pre-paid “burner” phone for calls, and occasionally carries it in a metal-lined wallet to avoid it being tracked. But as a busy mother of two she finds being out of reach of the cellphone network impractical.