Australian Attorney-General George Brandis has linked the Martin Place siege and the terrorist attack in Paris on Charlie Hebdo to the government's desire to pass legislation requiring telecommunications companies to retain customer data for two years.
This comes despite the fact that the man at the centre of the Sydney siege was well known to police, and France already has mandatory data-retention laws in place.
In an opinion piece in The Australian today, Brandis said the two attacks show that the "free and democratic West" faces a profound threat, and that the government has been acting in the introduction of the four pieces of national security legislation introduced into parliament in 2014.
The fourth so-called "tranche" of legislation will force telecommunications companies to retain an as-yet-undefined set of customer data for two years to be accessed by law enforcement and other government agencies without a warrant.
It will likely be debated in parliament in March, after the Joint Standing Committee on Intelligence and Security has completed its investigation of the proposals.
Brandis said that the legislation is "crucial", and needs to be passed as an "urgent priority" when parliament resumes.
"Access to metadata is vital to investigate terrorism and organised crime. The Bill does not propose any additional powers for national security agencies. It requires telecommunications companies to retain information they have routinely kept, but which they might not keep in future," he said.
Telecommunications companies dispute the government's argument that they will only be required to keep information that they have "routinely kept", arguing that the proposal asks for data to be held that never had been in the past, and in a format that is not of a kind they use.
The companies are pushing to have the mandatory data-retention period for IP addresses reduced down to six months.
Despite law-enforcement agencies claiming that retained data is "a fundamental building block" for investigations, none of the police agencies were able to outline to the parliamentary committee exactly how many criminal investigations had been aided by access to telecommunications data.
The issue of what such a scheme will cost, and whether it is the telcos or the taxpayer that bears the cost of mandatory data retention, has still yet to be worked out between the government and the telcos.
The Communications Alliance reportedly issued a questionnaire to its members on Christmas Eve with a deadline of this week to respond. The questions were said to have asked whether data retention would provide "operational benefits" to the telcos, and what the cost would be to extend the scheme out to three years, or reduce it to one year.
The passage of the legislation will likely require Labor support in the Senate. The party has voted for the previous tranches of legislation, but some within the party, including Shadow Attorney-General Mark Dreyfus and Shadow Communications Minister Jason Clare, have expressed reservation on the legislation as it stands today.
Brandis' own metadata was censored from release under Freedom of Information by Brandis' chief of staff, Paul O'Sullivan.
It comes as European, US, and Canadian security ministers have said that increased internet surveillance and tighter border checks are "urgently needed" to prevent attacks similar to that in Paris.
The gathering of interior and justice ministers at the French interior ministry was held before a massive anti-terror march in Paris that included dozens of foreign leaders.
A joint statement by the ministers -- representing 11 EU nations including France, Britain, Germany, Sweden, and Poland, as well as the European commissioner for migration and home affairs, and US Attorney General Eric Holder -- emphasised their "determination to fight together against terrorism".
They said it is "essential" that major internet providers cooperate with governments in closely monitoring and, if necessary, removing online content "that aims to incite hatred and terror".
They also want to "step up the detection and screening of travel movements of European nationals" leaving or entering the EU's external borders, and modify Europe's internal Schengen freedom-of-movement rules to widen information sharing and subject suspect passengers to greater checks.
They see a "crucial and urgent need" to establish an EU-wide database of passenger information for travel inside Europe and for flights leaving or entering the 28-nation bloc.
The proposed measures are to be discussed further at a February 12 EU summit focused on reinforcing security.
Holder announced a broader February 18 summit in Washington to be hosted by US President Barack Obama.
The steps were unveiled after three days of carnage in Paris by three gunmen who claimed allegiance to Al-Qaeda in Yemen and the rival Islamic State group.