A prominent Sydney barrister has killed himself weeks after being caught with child abuse material and having sexualised chats with minors.
Mark Dennis SC, 56, was searched at Sydney Airport on January 19 and found with a photo of a young boy and chats about wanting to rape a teenager after returning from Cambodia, where he ran a charity for disadvantaged youths.
He was granted bail two days later, was found dead at his home in Leichhardt. Police do not believe the death is suspicious and are treating it as a suicide, The Daily Telegraph reported.
Dennis previously worked as a solicitor for the Western Aboriginal Legal Service, and in 2017 wrote a paper on criminal law titled “Defending Child Sexual Assault in the Local Court”, which included advice on cross-examining child witnesses, and wrote extensively under “Dark Menace”, a play on his own name.
“Criminal trials are like pop music – every song has an underlying emotion (albeit sometimes a very simple emotion),” Dennis wrote in a November 2025 paper, his most recent, The Sydney Morning Herald reported.
“An allegation of child sexual assault brings forth the emotion that child sexual assault is a putrid crime committed by deeply evil people.”
In 2020 he founded the charity Reasonable Cause to help impoverished young people with literacy and scholarships in Cambodia, and visited the South East Asian country twice a year.
When he appeared in court after his arrest prosecutors said Dennis’s chats with at least two other people showed he had a “sexual interest in children under the age of 18 years”.
“There’s an awareness of laws around consent and a willingness to subvert those laws,” prosecutor Jon Kisch told the court.
“There’s a description of potentially a desire to rape a 16-year-old … I appreciate that’s as far as it goes, but certainly very disturbing chats.”
A Dropbox account linked to 12 devices was also found including a single photograph of a boy aged six to 10, but other images were believed to have been exchanged also.
Police also found an iPad in Dennis’s home, where he lived alone, that had a note on it suggesting it would self-delete if connected to the internet, and police argued against bail on the grounds Dennis may wipe evidence if released, but was released on bail by Acting Magistrate Robert Cook.
Header image: Mark Dennis SC (supplied).
