Dylan Voller was already a polarizing figure in Australia when the disturbing, violent and demonstrably false accusations against him began to appear on Facebook.
Mr. Voller had become famous overnight in 2016 after a television news exposé on the mistreatment of juveniles in the country’s criminal detention system broadcast a photograph of him, at age 17, hooded and strapped to a chair by guards. The image, likened by some to those of prisoners at Abu Ghraib in Iraq, shocked many Australians, prompting a national investigation.
Beneath articles about the investigation written by major Australian news outlets and posted to their Facebook pages, several commenters attacked Mr. Voller. Some made false accusations, including that Mr. Voller had raped an elderly woman and attacked a Salvation Army volunteer with a fire extinguisher, blinding him.
Instead of confronting the commenters directly, Mr. Voller sued the news media outlets, arguing that they were…