Two years ago, The Guardian's Paul Farrell wrote a piece showing that an Australian vessel engaged in policing our border against asylum seekers went deep into Indonesia's internal waters to do so. A government review of the incident had previously said the crossing into Indonesian waters was inadvertent. By showing how far the vessel had actually gone, Farrell's story cast serious doubt on this claim.
Since then, various parts of the Australian state have been doing all they can to discover who Paul Farrell's source for the story was. And Farrell has been using FOI law to shine a light on how this is happening.