Optus sent two emails to an incorrect address at the Department of Communications, alerting it of the Triple Zero outage on September 18, despite the telecommunications giant updating its system a week earlier to have emails sent to the department’s correct channels.

Appearing before a Senate estimates hearing on Wednesday, department officials confirmed that Optus was notified of the email change a week before the outage on September 11, and had updated its systems to reflect the change, but still sent emails about the outage to the wrong address.

The two emails, sent seven minutes apart to a defunct email address on the afternoon of September 18, understated the extent of the 13-hour crisis, and were not found until the department later scoured its systems. The office of Communications Minister Anika Wells was included in the emails and sought assurance from Optus that the Australian Communications and Media Authority had been informed, but did not contact the watchdog directly.

The first email, sent at 2.45pm, said “some customers in SA and WA are experiencing impacts to Triple Zero calls” and that the issue was being “worked through”. The second, sent at 2.52pm said the issue had been resolved and that only 10 calls had been impacted.

Optus had contacted ACMA at 2.40pm on the afternoon of September 18, stating that 10 Triple Zero calls had been affected. The call raised alarm bells at the watchdog, which requested additional information from Optus after employees felt the number of affected calls seemed low.

Notifications to the minister, department and ACMA all came after the outage was resolved.

Greens senator Hanson-Young said Optus CEO Stephen Rue – who was grilled at Parliament House on Tuesday – had told her in a private meeting that officials at the telco were aware of deaths resulting from the outage on the evening of September 18, and that Rue himself was aware by 9am on September 19.

She was critical of the authority’s limited attempts to investigate the issue after they were informed, saying: “We need a watchdog with teeth, we don’t need a lapdog.”

Similarly, Liberal senator Sarah Henderson expressed her concern with ACMA investigating the outage, saying it was “like putting Dracula in charge of the blood bank”.

It was not until September 19 that the minister, department and ACMA became aware of the extent of the outage, and the loss of lives associated with the network failure.

Speaking at Senate estimates on Wednesday, department secretary James Chisholm told senators that he “would not consider notification complete if it’s sent to the wrong place. So notification occurs when it is given to the right recipient. In this case, it was not.”

Hanson-Young grilled Chisholm on the fact that the email remained unread for over 24 hours, as department officials confirmed several times that the email inbox was not monitored. Officials only found the communications from Optus after they were notified of the outage on September 19 by ACMA.

The department said it had told telcos that the old email address would still be monitored, but that it should not be relied upon as an appropriate notification channel.

“That communication … was sent to the wrong address, which we have told industry a number of times is not to be used as a source of notification. We were not notified of the outage properly, and in this case it was by the regulator, until the Friday afternoon,” Chisholm said.

Chisholm repeatedly refused to answer a question from Hanson-Young on why an email forwarding system was not set up from the defunct email address. The deputy secretary said that was not the issue, but that Optus had failed to notify the correct address.

Kathleen Silleri, assistant secretary of the emergency communications section of the department, said all telcos, including Optus, were aware of the correct email address, noting the telco had “been using the correct email address for every other outage”.

According to the department, Optus had been notified of the changed email address on September 11, and had confirmed to the department that it had updated its IT systems to integrate the change on September 12. Official testimony showed that 272 emails had been successfully sent from Optus to the correct address between September 11 and October 8.

During her testimony, ACMA chief Nerida O’Loughlin said that the $12 million penalty on Optus following a November 2023 outage had not been a strong enough deterrent, despite being the largest infringement the watchdog had ever applied.

“We would expect that a substantial penalty would make a difference in a company the size of Optus. What is clear now is that it did not. We were confident at that time, and with the assurances that Optus gave us at that time, that they had made changes to their systems and processes that gave us confidence that they would move forward and not be in breach again,” O’Loughlin said.

The publication of the emails during Senate estimates led to a heated political attack against Wells during question time. Opposition Leader Sussan Ley described the emails as “secret”, suggesting Wells had been caught out in a lie about when she was aware of the outage.

Wells and her office repeatedly pointed to a September 22 press conference in which the minister said: “We and my department … were first emailed a notification that there had been an outage affecting 10 calls on Thursday [the 18th] afternoon.” At the time, Wells said she was not aware of the magnitude of the outage or the related deaths until the following day, in line with the testimony of both ACMA and her department.

The opposition line of attack on Wednesday followed Tuesday’s question time, where the Coalition criticised Wells for only legislating a Triple Zero custodian 17 months after an independent review had made the recommendation.

Hanson-Young will pursue a Senate inquiry into the event later this month, following the failure of the attempt in the House of Representatives.

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