Dennis Richardson, the former head of ASIO, has stepped down from his role as a special adviser to the royal commission on antisemitism.

On Wednesday evening, Commissioner Virginia Bell revealed Richardson’s unexpected resignation as the commission gears up to deliver its preliminary report by the end of April.

The royal commission was initiated by Prime Minister Anthony Albanese in the wake of the Bondi Beach terrorist attack. On December 14, two gunmen tragically ended the lives of 15 people during a Hanukkah celebration.

Bell acknowledged Richardson’s critical role, stating, “At the commission’s inception, I highlighted Mr. Richardson’s unparalleled ability to guide us on the necessary intelligence and security agency materials to evaluate their readiness and response to a terrorist event.”

She also expressed gratitude towards Richardson and his senior team members, Tony Sheehan, formerly of ASIO and the Commonwealth counter-terrorism office, and Peter Baxter, a past deputy secretary of the Department of Defence and head of AusAID, noting that substantial progress has been made on the interim report.

Bell extended her appreciation to Richardson for his significant contributions to the commission’s efforts.

Her statement did not provide reasons for Richardson’s resignation.

Albanese’s government initially refused to call a royal commission into the Bondi massacre, instead tapping Richardson to head a review of the adequacy of intelligence and law enforcement agencies before the attack.

Following weeks of political pressure, Albanese relented and announced a broader inquiry to be headed by Bell, a former High Court judge, to investigate antisemitism and any failures in the nation’s intelligence services.

Mr Richardson’s review was folded into the new royal commission.

The inquiry is due to deliver its interim report to the government by 30 April.

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