Victoria Police has served a cyberbullying intervention order via Facebook, after unsuccessful attempts to reach the accused by phone and in person.
The man was a "prolific Facebook user" who had allegedly threatened, bullied and harassed a former partner online.
Police were approached by the victim in August, but were unable to locate the accused by traditional means.
In what police believe to be an Australian first, the accused was served with an interim intervention order, extract, explanation, contacts and a video of Leading Senior Constable Stuart Walton via a Facebook private message.
The accused was ordered not to publish any material about the victim online, and not to contact the victim "by any means", including phone and e-mail, except through the police or a lawyer.
"If you do not obey this order, you may be arrested and charged with a criminal offense," Walton said in the video.
The accused did not attend Court as ordered, and police were unable to confirm that the message had been read. However, a Victorian Court Magistrate upheld the order indefinitely and a final order was served via Facebook.
Police finally succeeded in contacting the accused after the final order was served, and ascertained that he had read both interim and final documents via Facebook and agreed to comply.
"Internet bullying, stalking and intimidation are taken very seriously by Police. In this instance we were able to deliver justice through the same medium as the crime committed," Walson stated.
"Police will always pursue traditional means to enforce the law and to protect the community - but we won't shy away from innovative methods to achieve positive outcomes, either."
Facebook claims to take users' privacy "very seriously", and works with law enforcement "to the extent required by law".
In May, the Australian Federal Police called for Facebook to establish a local law enforcement contact who would be immediately accessible to Federal, state and territory agencies.