The announcement came hours after Premier Mike Baird revealed he had written to Prime Minister Malcolm Turnbull urging him to significantly strengthen Australia's counter-terrorism laws, including lowering the age threshold for control orders. The disclosure followed the murder of police accountant Curtis Cheng by 15-year-old Farhad Jabar at Parramatta. In a letter, Mr Baird and NSW Police Minister Troy Grant said that if the states and territories could not agree on changes to lower the age threshold for control orders, NSW would consider introducing its own legislation. This would allow state-based control orders to be applied to people as young as 14. However, it is understood that discussions between NSW and the Turnbull government about lowering the age threshold for control orders and other anti-terrorism measures had been well advanced.

As Mr Baird met Muslim leaders on Monday to discuss responses to Mr Cheng's killing, he and Mr Grant revealed they had written to Mr Turnbull outlining proposals to "assist counter-terrorism investigations and address the changing terrorism threat". As well as lowering the age threshold for Commonwealth control orders they argued existing powers hindered the ability of police to adequately question and detain terrorism suspects. They wanted changes that would allow arrest and detention "where there is a reasonable suspicion that the person is involved in an imminent terrorist attack". Under the proposal – modelled largely on British laws – a terrorism suspect could be arrested and detained for an initial period of up to four days without charge, and this may be extended by the courts to up to 28 days. Under Commonwealth legislation, a terrorism suspect may at present be arrested and detained for an initial four hours, which may be extended by a court to up to eight days.

Police would also be given an extended period to question a detained terrorism suspect for "evidential purposes", well beyond the present 24-hour period. As well, a mechanism would be established to allow a judge to rely on "sensitive information" that may be withheld from the subject when deciding whether to issue a control order. "The act of terrorism at Parramatta was a clear demonstration that we need to strengthen powers to prevent terrorist acts and improve law enforcement's ability to respond to the changing terrorism environment," Mr Baird said. "The terrorism environment in Australia is shifting quickly, with younger people becoming involved, and we need to respond just as swiftly. "I look forward to progressing this with our Commonwealth counterparts who have chief responsibility for terrorism laws."

Mr Grant said the NSW government "is committed to equipping our law enforcement agencies with the tools they need to prevent terrorism, gather evidence in response to a terrorism act and to protect society from those who intend harm". In his statement, Senator Brandis said the federal government looked forward to "continuing close consultation with the NSW and other Australian governments on these issues". "As the threat evolves so will our response to ensure that our police and security agencies have the powers they need to keep our community safe," he said.