The study focused on internet relay chat or IRC chatrooms, which are among the most popular chat services but offer widely varying levels of user security.
The researchers logged into various chatrooms under female, male and ambiguous usernames, counted the number of times they were contacted and tracked the contents of those messages. The researchers also determined that simulated users or "bots" are not behind most of the malicious messages.
The matter was referred to Tasmania Police who then searched his home and seized computer equipment and hard drives.
The court was told Cook used the chatrooms as a substitute to personal sexual encounters and he usually claimed to be younger than he was.
The boy is tall for his age, but slight, with olive skin, a long crooked nose, and dark, intelligent eyes framed by thick black brows poised for flight. One in the chest—that was the light wound—and another in the abdomen, six inches deep, which pierced his kidney and liver and necessitated the removal of his gallbladder.
He was charged with 17 counts of using a carriage service to send indecent communications to a person under 16 years of age, 10 counts of using a carriage service for child pornography material and one count of possessing child exploitation material.
The court heard the then-28-year-old computer programmer sent messages graphically describing sexual acts to girls as young as 12 over six months in 20.
Cook justified his behaviour on the high probability the people he was talking to were adults and not children, the court heard.
In sentencing, Justice Shan Tennent rejected that argument and said she was satisfied Cook "deliberately targeted young females on a regular basis until he was caught".