Lindt inquest findings expected in 2017

The findings of the long-running inquest into the fatal Sydney Lindt Cafe siege are expected to be handed down next year.

While wrapping up the inquest's last public hearing on Wednesday, Coroner Michael Barnes declared it was not his role to lay blame over the tragedy.

Detailing facts and instructing authorities on ways to prevent such events happening again would be his primary focus, Mr Barnes said.

The question of whether Australia's intelligence agency ASIO could have done more to stop gunman Man Haron Monis before the fatal siege in December 2014 will likely go unanswered.

Evidence relating to ASIO's involvement is unlikely to be publicly released when the coroner releases his findings, the inquest was told.

The inquiry has been examining what ASIO knew about Monis and whether it should have taken action against him before he staged the stand-off.

It's also examined whether Monis should have been detected, kept under surveillance or on a security watch list.

The roles Australian Defence Force (ADF) officers performed during the siege as well as questions about whether the force should handle all domestic terror matters were also investigated.

Mr Barnes said he regrets the pain the inquest caused the families of slain hostages Katrina Dawson and Tori Johnson as well as those who survived.

"The inquest was obliged to start before many affected by the deaths could have been emotionally ready. That must have added to their pain and that is something I deeply regret," he said.

The legal teams at the inquest are expected to hand in their final submissions by December 23.