Senior Lindt negotiator did 'Islam 101'

A senior negotiator involved in the deadly Lindt Cafe siege says he had never previously dealt with a terrorist and would have called for more resources if he had his time again.

The detective senior sergeant, identified only as "Reg", told the coronial inquest into the siege he had four weeks' negotiating training in the late 1990s, and later completed "Islam 101" at a national counter-terror course.

In those years, he said, not everybody was familiar with Islam and religious training was provided to bring people up to speed.

"(It was) in essence a 101 in trying to understand Islam - the faith and the religion," he told the inquest on Thursday.

Reg had never previously been confronted with a confessed terrorist or had to deal with a situation involving more than three hostages.

When he learned there was a gunman with a backpack and suspected Islamic flag holding a large group of people hostage inside the Lindt Cafe, he knew the December 2014 incident presented a unique challenge.

"It took a whole new twist ... in that sense, it was going to be a big job," Reg said.

In hindsight, he told the inquest his unit would have benefited from more help.

"If I had my time again, and touch wood I don't, I would definitely have called for more resources," he said.

Reg said not having officers stationed at all major media outlets hampered the flow of information coming through to the negotiating team.

Gunman Man Haron Monis had offered negotiators a possible bargaining chip early in the afternoon when eh asked for an Islamic State flag in return for the safe release of one hostage, but the demand was never acted upon.

Negotiators spotted another possible breakthrough later that evening, when Monis demanded the lights in Martin Place be turned off.

Reg said he passed the request on to his superiors, but never advocated for the course of action, or followed up to find out how it was progressing.

Negotiators never spoke directly with Monis throughout the 17-hour siege - a central pillar of their "contain and negotiate" strategy - but instead communicated with him through hostages.

"That impaired your ability to try to influence his behaviour?" counsel assisting Jason Downing asked.

"Not being able to speak to him directly, of course," Reg replied.

Officers eventually stormed the cafe shortly after 2am on December 16, after Monis shot cafe manager Tori Johnson dead from point-blank range.

Barrister Katrina Dawson was killed by a police bullet in the raid, while Monis also died.

The inquest continues.