Optus to be called before senators on Monday to explain triple-0 failure

Executives from Optus will be called to appear at a Senate hearing on Monday, where they will be grilled on their handling of September's fatal triple-0 failure.

The public inquiry into the system, a joint initiative of the Greens and the Coalition, was green-lit by the Senate on Tuesday afternoon and will probe the actions of telcos, government agencies, and the communications minister.

At a meeting of the inquiry's secretariat on Tuesday evening, senators agreed to hold the first day of hearings in Parliament House next Monday, with Optus executives to be called first.

While committee members are hopeful the company's executives will agree to attend, the Senate retains powers to compel their attendance should they decline.

The telco has apologised to those affected by its hours-long failure to realise that a routine systems upgrade had disrupted the emergency service in Western Australia, South Australia, and parts of New South Wales, which resulted in three deaths.

But there remain several gaps in the known chain of events. Last month, senators heard from government officials who said the telco had at first underplayed the severity of the failure, reporting that only 10 calls had been affected.

It took more than a day to alert the regulator ACMA, the communications department, and minister Anika Wells that the number was in fact 600, and that deaths had occurred.

That notification reached the minister only minutes before Optus chief executive Stephen Rue held a public press conference late on a Friday afternoon, although Ms Well's office had been told of 10 failed calls the day before.

Greens senator Sarah Hanson-Young, who chairs the parliamentary committee which will oversee the inquiry, said its purpose was to "hold Optus to account and suggest a pathway forward for further reform".

Liberal communications spokesperson Melissa McIntosh said "no stone must be left unturned" by the inquiry.

"We are coming into disaster season, and this inquiry, which starts on 3 November, must review every nook and cranny of the ecosystem to ensure the safety of all Australians and their ability to call triple-0 in their greatest moment of need."

Fellow Liberal Sarah Henderson, a former communications minister who is now a backbencher, said the inquiry was "vital to uncovering the truth" and that Ms Wells should appear.

"The role of the minister in safeguarding the integrity, resilience and public confidence in the triple-0 system is central to [the] inquiry," she said.

Bill for triple-0 'custodian' passes

Earlier on Tuesday, Labor passed legislation to establish a "custodian" for the triple-0 system. This was a recommendation of a past review of the system, which followed a different Optus outage.

The custodian would have stronger information-gathering powers than currently exist, although experts have said the office is unlikely to have prevented the Optus outage had it been in place already.

Labor agreed to triple the maximum penalties for breaches of triple-0 obligations from $10 million to $30 million, proposed by the Greens.

"With these new powers for the Triple Zero Custodian, there will more active [sic] and effective monitoring make sure [sic] this vital service meets their needs," Ms Wells said in a statement.

"Australians must have confidence that Triple Zero will be there when they need it most."

Another bill to enact other outstanding recommendations from the same inquiry is before the House of Representatives.