But Tony Abbott conceded that even if the 50-year-old had been on a watch list, officials might not have been able to prevent the bloody hostage crisis that unfolded over 16 hours in the centre of the city and which claimed two innocent lives.
“These are questions that we need to look at carefully and calmly and methodically to learn the right lessons and to act upon them. That’s what we’ll be doing in the days and weeks ahead.”
He added: “Could it have been prevented? Even if this individual, this sick and disturbed individual, had been front and centre on our watchlists, even if this individual had been monitored 24 hours a day, it’s quite likely, certainly possible, that this incident could have taken place.”
Monis, a self-styled Muslim cleric, rose to notoriety in Australia after he was convicted of writing offensive letters to the families of soldiers killed in action.
He pleaded guilty but subsequently fought the charges, even mounting a High Court challenge claiming the government was infringing on a constitutionally-implied right to “freedom of communication on political and governmental matters”.
That challenge was rejected by Australia’s chief justice Robert French just three days before the siege began.
Monis was granted bail in the New South Wales local court by magistrate William Pierce almost a year to the day before he picked up a gun, walked into the Lindt Chocolat Cafe in Sydney’s busy financial and legal district, and unfurled a black flag bearing an Islamic affirmation of faith.
The lawyer representing him on that occasion has since described the murder accessory case against him, which related to the killing of Monis’s ex-wife Noleen Hayson Pal, as weak.
Fairfax Media has reported that Monis’s bail was refused when he was re-arrested this year to face a string of sex and indecent assault charges stemming from alleged attacks on a woman during “spiritual healing” sessions, but he was released on bail in May, days after the New South Wales government introduced controversial changes to bail legislation that have since been reviewed.
New South Wales attorney-general Brad Hazzard said that under amended bail laws due to come into force at the end of January, “an accessory to murder before or after the fact would be forced into a situation of having to show cause as to why they should get bail”.
As legal commentators debate whether the tweaked laws would have kept Monis off the streets, mourners and well-wishers have flocked to Sydney’s Martin Place to offer flowers and tributes to the hostages.