Heather Brooke, whose FoI campaign helped expose the MPs' expenses scandal, has accused modern journalism of becoming "morally bankrupt" and having lost touch with its role as a champion of the public.
Brooke, speaking at City University, where she is a visiting professor, said journalism needed a "public purpose" and argued that over the past few decades media organisations had businesses first and foremost businesses.
She claimed that the desire of journalists to change the world had been usurped by a new type of journalism that was about marketing, PR and selling products and said: "The ultimate moral bankruptcy of modern journalism is that it has forgotten its heart, its core function, which is serving the public."
Brooke argued that the media had become "bamboozled by marketing and PR" and journalists no longer looked at courts, schools, and local councils - civic life - because it had fallen out of fashion.
Describing herself as a "cheerleader for resurgence of civics," Brooke warned that "when news is treated like just another widget in the production factory process it loses its purpose."
Brooke argued that the growth of new media - "where anyone can be a journalist" - had caused "an identity crisis" in mainstream journalism. But she argued that professional journalists were needed as curators and verifiers of news and the public would turn to media it knew could be trusted.
"Journalists will lead the way if they stay close to the people. We need to remember the public," she said.
Asked about WikiLeaks, Brooke replied that she supported the philosophy behind the whistleblowing website but thought its founder, Julian Assange, was "a morally bankrupt individual".
She claimed: "Julian made himself the star attraction and didn't let the material speak for itself and undermined the gravity of what it said."
Asked about self-regulation of the press in the UK, Brooke said it was "a totalitarian idea that you need to regulate the press to make it behave" and said what was important was the relationship between the press and its readers.
Brooke told another questioner, who asked darkly about suppression of stories about City University in its own media, that City was subject to the Freedom of Information Act...Over to you City University journalism students.
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