Ian Fackender had struggled with schizophrenia for almost 15 years when he was shot by police after an altercation in 2017.

Key points: 35 people shot by NSW police in last 20 years

35 people shot by NSW police in last 20 years 19 of those had a mental illness

19 of those had a mental illness All police have received a day's training on dealing with mentally ill people in a crisis

All police have received a day's training on dealing with mentally ill people in a crisis Greens MP David Shoebridge says that training is laughable

He is just one of 35 people shot dead by NSW Police in the past 20 years and, according to newly released police data, more than half of them had a mental illness.

"Now that we've got the data, it does seem … people with mental illness, all too often, are the people being shot and killed by police," said NSW Greens MP David Shoebridge, who obtained the data through the Government Information Public Access Act (GIPAA).

He believes an under-resourcing of mental health facilities and a lack of police training on mental health are the key factors.

'He was tasered twice and it didn't work'

Mr Fackender was a father of six.

"He was quite happy around his family. He was planning a trip up to see his youngest daughter in Queensland," his mother Sue told 7.30.

"He loved his grandchildren."

But his mental health took a severe blow 15 years ago, when his wife lost a baby at 36 weeks.

"He just seemed not quite right, just saying a few things that didn't make sense." Sue said.

"The first time he got help was when he really became quite psychotic and he was put on medication."

Ian Fackender died when he was shot by police in Bathurst.

Mr Fackender was diagnosed with schizophrenia but he struggled with the side-effects of his medication and sometimes chose not to take it.

On the day he was shot, Mr Fackender was five days overdue for a monthly injection of medication.

He had not responded to phone calls from his family and mental health workers, so the medical team called the police for help.

When Mr Fackender refused to answer the door, police let themselves in with a key Mr Fackender's mother had given them.

"Ian was asleep, or listening to music, he had his headphones on, and they went over and they lifted up his quilt and they saw that he had his Star of David sword, which, when he was unwell, that was his protection against everything," Sue said.

"When he saw them he grabbed it, I don't know whether he was waving it round or what was happening.

"The police officers then tried to taser him. He was tasered twice and it didn't work. And they started to retreat.

"And the police officer must have had his gun drawn — and he fired. Fired five shots into Ian."

'What's changed in 20 years?'

Danukul Mokmool, (left) with his brother and mother, was shot dead by police outside Sydney's Central Station. ( Supplied: Charlie Huynh )

It was Danukul Mokmool's death at Central Station that prompted Mr Shoebridge, to look more closely at the number of mentally ill people being shot by police.

"When I saw the fatal shooting at Central Station of what looked like a clearly mentally ill man surrounded by police, holding a pair of scissors, it immediately brought to mind the death of Roni Levi on Bondi Beach," he said.

"Whilst 20 years separated them, it didn't seem like a lot had changed in terms of the police reaction.

"I thought, 'Well, who's tracking the data? What's changed in those 20 years?'"

So he requested data from NSW Police.

"I simply asked for the names and numbers of the people who had been killed through the use of police firearms," Mr Shoebridge said.

Of 35 eligible* names provided, 7.30 has established at least 19 people (54 per cent) had a mental illness.

Mr Shoebridge believes the high proportion of mentally ill people on the list is driven by two factors.

"We've got a tragic under-resourcing of mental health facilities, and it's not just in NSW, that's a nationwide problem," he said.

"That means that frontline police are the frontline responders and those primarily relatively junior police are going out there, dealing with mentally ill people and, to be quite frank, they haven't got the training and they haven't got the support.

"You put those two things together, you have a very potent, tragic, often-fatal mix."

'It's a very complex space ... we're not hiding from oversight'

NSW Police Commissioner, Mick Fuller, would like zero police shootings. ( AAP: Dan Himbrechts )

NSW Police Commissioner Michael Fuller says the over-representation of people with a mental illness in police fatalities does not surprise him.

"The test of our success, unfortunately, can't be around a trend up or a trend down," he told 7.30.

"Clearly I want the trend to be zero.

"But for mine, it's about the root cause analysis — is there anything else that we could have done? If there is then we will do it."

He has promised full transparency about the use of police fatal force in the recent shootings.

"I just want to give the community of NSW an assurance that we are not hiding from oversight in terms of the way we use force," Commissioner Fuller said.

"But in many cases, whilst we will get recommendations from the coroner and things that we can improve, rarely has there been a finding by a coroner or otherwise that it was an unlawful shooting — as tragic as that may be."

Since 2014, all police in NSW have received one full day's training, through the organisation's Mental Health Intervention Team, in how to approach mentally ill people in crisis.

Police said the training focuses on de-escalating situations before they reach crisis point.

Approximately 300 officers a year take part in a further four-day course.

"The idea that one day's training on mental health will appropriately skill police constables to deal with the repeated interactions they have with mentally ill people in the community is laughable," Mr Shoebridge said.

Commissioner Mick Fuller says while mental health should always be part of the assessment officers make when facing a situation, there are other factors.

"If somebody is in direct threat of being killed by that person, then whether it's mental health or substance abuse, quite often police have to make a split second decision to take a life to save a life."

* The ABC removed 3 incidents from the data — two police officers accidently shot during operations and a person who was not the target but was hit by ricocheting shrapnel from a police firearm.