Brian Cathcart, professor of journalism at Kingston University, expresses exactly why the phone hacking scandal at the News of the World Matter so much.

Editors who routinely invoke the public interest when it suits them have in this case systematically abused the public interest. One leading player in the story has been in Downing Street for nine months; another dominates our media landscape; a third is our most powerful police force. If their conduct is not a matter of public interest, what is?

Absolutely. The point being that subterfuge – a deceit in order to reach your goal – is only ever acceptable by a journalist if it is overwhelmingly in the public interest. According to the steady flow of revelations coming from the high court, the hacking of mobile phones by the News of the World, and likely other newspapers, hasn’t ever been in the public interest. Not even once. Prince William’s doctor’s appointment is not in the public interest.

That’s why phone hacking is so morally and professionally wrong.