8 February - Immigration Minister Amanda Vanstone announces a closed inquiry to be headed by former AFP commissioner Mick Palmer, to investigate how Cornelia Rau came to be held in solitary confinement at Baxter Detention Centre and why she did not receive treatment despite suffering from schizophrenia.
9 February - Queensland Premier Peter Beattie releases an edited transcript of an interview between Cornelia Rau and officers at the Brisbane Women’s Correctional Centre on July 5, 2003.
10 February - Queensland Premier Peter Beattie apologises for the failure of his agencies to properly care for Cornelia Rau.
11 February - Immigration Minister Amanda Vanstone admits that criminals who have finished their prison sentences and are awaiting deportation are being held among asylum seekers at the Baxter Detention Centre.
13 February - Federal Treasurer Peter Costello breaks ranks with Prime Minister John Howard and says he and the government are sorry for the way Cornelia Rau was treated.
26 February – The ALP government of Geoff Gallop is re-elected in Western Australia for a second term.
27 February - Immigration Minister Amanda Vanstone announces an extension of the Rau inquiry from original date of March 24. Neil Comrie, the former Victorian Police Commissioner, is recruited to help Mick Palmer in the inquiry investigations.
22 March - Stuart Copeland, the Queensland Shadow Minister for Health, raises the issue of Doctor Jayant Patel's clinical practice during Question Time in the Queensland Parliament. Copeland had been alerted to Patel's inadequacies by Toni Hoffman, a nurse at the Bundaberg Base Hospital.
25 March - Rob Messenger, the National Party Member of Parliament for Burnett, raises the matter of Doctor Jayant Patel in a speech to the Queensland Legislative Assembly. He calls for Patel's suspension.
3 June - The COAG meeting between the State Premiers and the Prime Minister is held. The Premiers agree to disagree with the Prime Minister on industrial relations, but make a commitment to the establishment of a national system of apprenticeships to address the skills shortage.
28 June - Three suspects in a 2002 gang rape in Hurstville finally arrested in dawn raids in New South Wales.
29 June - Rain brings drought relief and flooding across New South Wales.
New South Wales Supreme Court finds no evidence of neglect against Westmead Hospital in the Rhiannon Richards brain damage suit, leaving her family to pay both sides' legal costs.
New South Wales health authorities warn parents of an outbreak of whooping cough across the state, urging parents to immunise their children.
Former Federal Labor Opposition Leader, Mark Latham's autobiography is released, causing uproar in the Labor Party.
14 July - Following the release of the Palmer Inquiry report, Prime Minister John Howard and Immigration Minister Amanda Vanstone apologise to Cornelia Rau, who was mistakenly held in detention for 10 months, and to Vivian Solon, who was deported to the Philippines. The 200-page report identified systemic weaknesses in the Department of Immigration which contributed to Ms Rau's detention, the failure to establish her identity, and to meet her mental health needs. The report says that those same mistakes were made in Vivian Solon's case.
21 August – Michelle Leslie is arrested in Bali after being found with two ecstasy pills in her handbag at an open-air dance party just outside of Kuta. She is found guilty, and sentenced to three months in prison on 18 November, but is released on 20 November as she had already served her sentence.
25 May – Graham Kennedy dies at age 71. The network on which most of his shows aired, the Nine Network, passes up the offer to broadcast his funeral & the Seven Network arrives, axes Nine's coverage and Seven picks it up and wins it. Nine does eventually show parts of the funeral live.
26 June – Douglas Wood is interviewed by Sandra Sully about his time as a captive after Network Ten pays a reported $400,000 for an exclusive interview.
15 August: Big Brother: Greg Mathew, along with twin brother David Mathew, also known as "The Logan Twins" is announced the winner of the fifth series.
4 March – First day of the Australian Track & Field Championships for the 2004–2005 season, which are held at the Sydney Olympic Park in Homebush. The 10,000 metres (men and women) were conducted at the Zatopek Meet in Melbourne, Victoria on Saturday 4 December 2004. The relays were conducted at Canberra on Sunday 6 February 2005.