On Tuesday, Simon Fleming, 41, was cleared of committing a terrorist act on the grounds of mental illness.

Forensic psychiatrist Dr Adam Martin told the jury last week that Mr Fleming was experiencing psychosis when he donned black combat fatigues and fired bullets into the air, before he took two men hostage in a dive shop in November 2021.

He eventually surrendered to police after an hour-long standoff. No one was harmed during the incident.

Defence barrister Leah Rowan and lawyer Aaron Kernaghan maintained Mr Fleming was impaired by mental illness at the time and this impacted his understanding of the events.

The Crown previously alleged Mr Fleming's actions were a case of terrorism, motivated by a desire to intimidate the Australian public and the government.

However after weeks of "distressing" evidence was laid bare to the jury - including triple-0 calls, extremist ideology contained in a manifesto, and a chilling police interview - the Crown conceded on Monday the defence of mental illness was available to Mr Fleming.

NSW Supreme Court Judge Helen Wilson thanked the jury members for their service, saying they may have found it a strange experience as it paused multiple times last week.

"You may have found this an unusual trial, there's been some stops and pauses ... and it doesn't usually happen that way," Justice Wilson said before ordering the jury to return a special verdict of not guilty.

The remaining 11 charges, including firing a firearm in a manner likely to injure, taking and detaining a person to gain advantage, and possessing a prohibited firearm, will also be dealt with on mental health grounds.

Speaking to reporters outside the Supreme Court in Parramatta, Mr Kernaghan criticised prosecutors for pursuing the terrorist charge, adding Mr Fleming had lived in the community with a serious mental health problem for some time.

"It's a serious thing to accuse someone of terrorism ... it's one of the top charges you can be accused of," Mr Kernaghan told news.com.au.

"I'd like to think, in this country, that if a prosecution is going to mount a case like that against a citizen, they have absolutely iron-clad evidence."

Week 1:

Prosecutor James Renwick told the jury in the years before the incident, Mr Fleming was overtaken by the belief that political correctedness, feminism and Marxism would lead to a "white genocide".

The court heard Mr Fleming laid out his beliefs in a manifesto found on a USB he was carrying on the day of his arrest. Read the full story here.

Details of the manifesto continued to be aired, while the jury also watched a chilling police interview with Mr Fleming following his arrest. He appeared detached as he told detectives he "wasn't trying to hurt anybody".

"I was just trying to get people's attention," Mr Fleming said, adding he was withdrawing from anti-psychotic medication at the time. His memory of the events was patchy, but he denied ever telling his hostages he was a terrorist. Read the full story here.

Dr Martin later told the jury his blank expression was described as "blunting" - a well-recognised symptom of schizophrenia.

Windang Dive and Spearfishing owner Keith Woods gave evidence of being held hostage inside the store after Mr Fleming shot bullets on Windang Rd. Read the full story here.

Week 2:

Dive shop employee Neil Hay was also held hostage for an hour, and was praised by Justice Wilson for his kindess on that day. Read the full story here.

Mr Flemings mother, Carol Fleming, paused multiple times as she gave evidence about her son's struggle with mental illness dating back to 2008. Mrs Fleming said she contacted multiple services to help her son to no avail. Read the full story here.

Week 3:

Forensic psychiatrist Dr Adam Martin said Fleming's alleged actions on the morning in question were "very closely associated" with psychosis. Read the full story here.

Week 4:

The Crown conceded the defence of mental impairment was available to Mr Fleming. "There is no dispute [Mr Fleming] was seriously psychologically ill on that day," Justice Wilson told the jury on Tuesday.

After the Crown case collapsed, the jury was ordered to return a verdict that Mr Fleming was not guilty on the grounds of mental impairment.

This means the acts have been proven, but Mr Fleming has been ruled not criminally responsible.

He will now be dealt with under mental health law, which a jury will not be involved in.

Justice Wilson ordered a special verdict that Mr Fleming be transferred to a forensic hospital.

The matter will return to court next week.

Read more Illawarra court and crime stories here.

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