A reporter at Tuesday morning's press conference with the NSW Premier posed the uncomfortable question about the Martin Place siege that will now surely become the subject of further investigation: "How was this gunman free on bail?".

Man Haron Monis, a self-styled sheikh shot dead by police in the early hours of Tuesday morning, was before the courts on two separate and serious matters: more than 40 sexual assault charges involving seven alleged victims; and as an accessory to the murder of his former wife.

He died seven years after first coming to the attention of police, when he penned poisonous letters to the family of Australian soldiers killed in the Middle East.

Monis, 50, was given bail at Penrith Local Court on December 12 last year after being charged with being an accessory before and after the fact to the murder of his ex-wife and mother of their two children, Noleen Hayson Pal, 30.

Ms Pal was allegedly stabbed 18 times and set alight in an apartment stairwell in Werrington on April 21, 2013.

Monis' then partner, Amirah Droudis, was charged with Ms Pal's murder

Magistrate Bill Pearce granted the pair bail after a hearing lasting more than three hours.

"It is a weak case," he said, according to media reports at the time.

Each of the accused had an alibi, the witness statements varied significantly, they didn't have anywhere else to go and they weren't a threat to the public, the magistrate said.

"If there is a threat it was to this woman who was murdered."

Monis and Ms Droudis were granted conditional bail and ordered to report daily to Campsie Police Station.They were also ordered to surrender their passports and not go within 500 metres of a point of overseas departure and not to contact "the prosecution witness".

Ms Droudis' bail conditions also stipulated that two people had to agree to forfeit $100,000 should she fail to meet her bail conditions. She was also ordered to reside at a place in Wiley Park.

Monis had to find a person to deposit $10,000 cash and was ordered to reside at a place in Belmore.

In January this year, a 27-year-old woman complained to police that she had been sexually assaulted by Monis, after attending "spiritual healing sessions" in response to an advertisement placed in newspapers aimed at the Fijian-Indian, Macedonian, Spanish and Chinese communities.

That complaint triggered a police investigation, which saw Monis charged on April 14 with three sexual assault charges against one woman. The charges were sexual intercourse without consent and two charges of assault with act of indecency.

The woman was visiting him at a property in Station Street, Wentworthville, in August 2002. He appeared before Magistrate Christine Haskett at Kogarah Local Court. He was refused bail.

On May 26, he was granted bail at Parramatta Local Court by Magistrate Joan Baptie. The conditions placed on him in December 2013 were reinstated although he was to live at an address in Wiley Park.

On October 10, he was charged with a further 40 sexual assault charges against six women. This included 22 counts of aggravated sexual assault, 14 counts of aggravated indecent assault, one count of aggravated act of indecency, one count of sexual assault and two counts of assault with act of indecency. The women were visiting him at Wentworthville where he was offering services as a "spiritual healer". His bail was continued by Magistrate Dorelle Pinch.

He was due to appear in Penrith Local Court on Friday, December 12, but this was vacated and changed to February 27, 2015.

Premier's distress

Addressing the press on Tuesday morning, NSW Premier Mike Baird gave an assurance he would answer all questions on the siege, and its tragic conclusion.

Mr Baird was quizzed on "reports that this guy was out on bail. Are you concerned that potentially that allowed for this to happen?"

"Well, I'm concerned that there was a vicious, horrendous attack that has taken place in the heart of our city, and there are many questions that will come in the coming hours, days and weeks," Mr Baird said.

"What I can assure you is I will answer every single one of them.

"We will get to the bottom of events and we will do everything possible to ensure we do not see happen again in this city what we saw in the last 24 hours."

'Weak case'

According to reports of last December's accessory to murder bail application, Magistrate Bill Pierce said at the time there were significant flaws in the Crown's case.

The Crown alleged that Monis went to elaborate lengths to keep himself away from the crime, including faking a heart attack that led to a staged car accident on the day.

He also faked a robbery of his Werrington flat and took out contents insurance on the specific items that he reported stolen on the day of the murder, the Crown said.

The court heard Mr Monis and Ms Pal were involved in a bitter custody battle at the time of her death.

Long-running battle

Monis recently likened himself on his own website to Wikileaks founder Julian Assange, claiming the most recent charges against him were laid for "political reasons".

His website also carries a quote, posted earlier this month, stating: "I used to be a Rafidi, but not any more. Now I am a Muslim, Alhamdu Lillah."

It has been Monis' ongoing legal battle over his conviction for penning the poisonous letters to the families of dead Australian soldiers between 2007 and 2009 that has consumed him.

It is understood Monday's siege followed an unsuccessful, last-ditch attempt in the High Court on Friday, December 12, to have the conviction overturned.

Monis was sentenced to 300 hours of community service and placed on a two-year good behaviour bond for the "offensive and deplorable letters" sent with the assistance of his then girlfriend, Amirah Droudis.

They were sent to the families of Private Luke Worsley and Lance Corporal Jason Marks, who were killed in Afghanistan in 2007 and 2008.

He also sent a letter in 2009 to the family of the Austrade official Craig Senger, who was killed in the bombing of the Marriott Hotel in Jakarta in 2007.

Monis claimed the letters were his own version of a "flower basket" or "condolence card".

Bree Till, widow of Sergeant Brett Till, killed while defusing a bomb on March 12, 2009, said at the time of his conviction: "We sat reading these letters [which] made out to be something supportive but then the juxtaposition of this man accusing my husband of being a child-killer while dictating how I should raise my children. It was scary," she said.

He fought the validity of the charges all the way to the High Court arguing they were political and only sought to persuade the families to oppose Australia's military involvement in Afghanistan.

But when he lost that battle, and had to stand trial, he pleaded guilty to all 12 charges against him in August 2013.

'Covered in excrement'
Monis claimed he suffered poor treatment while in prison, Manny Conditsis, a Sydney lawyer who represented Monis last year said.

"He was put through let's say some very unpleasant events, involving matters of excrement over himself and his cell," he said.

"This is a one-off random individual.

"It's not a concerted terrorism event or act.

"It's a damaged goods individual who's done something outrageous."