He was found dead in his room at 3 Phillips St, Kensington, following the fire on April 15, 2022.
The fire started in a pile of clothes in the corner of Mr Bonisch’s room, and there was evidence of an accelerant on them.
Coroner Marcus Elliott said Mr Bonisch was hit by a car in 1993, after he stepped off a tram in Melbourne leaving him with a serious head injury.
He had also been diagnosed with schizo-affective disorder and depression.
An occupational therapy functional assessment found he had “a significant skill base for living independently”, so he was placed in a room at the Phillips St boarding house, where he lived on his own for about four years.
His treating psychiatrist said Mr Bonisch appeared to be relatively happy with his accommodation and enjoyed having more freedom and independence than was previously possible in supported accommodation.
On the night of the fire, the fire alarms in the building sounded, and all the other residents evacuated safely except Mr Bonisch.
Coroner Elliott said investigations by police and Fire and Emergency New Zealand (Fenz) produced no evidence to show the fire started because of any property defect or electrical issue.
“The fire started in a pile of clothing in Mr Bonisch’s room.
“He was alone in the room when it started.
“It is more probable than not that the fire started due to something Mr Bonisch did.”
However, the coroner said there was uncertainty about what Mr Bonisch had done.
“Low levels of acetone, ethanol and isopropyl alcohol were found on the T-shirts which were in the pile of clothing where the fire started.
“While these are flammable solvents, they are also emitted from the human body.
“The ESR scientist expressed the opinion that these were likely to be from the wearer of the clothing, rather than an external source.
“Another possibility is that the solvents were present due to an accelerant which had been put on the clothes,” Coroner Elliott said.
“If they resulted from the presence of a liquid such as methylated spirits (which had been seen in Mr Bonisch’s room), this liquid may have been accidentally spilled on the clothing, or the clothing may have been used to wipe it up.
“The evidence is insufficient to support a finding that Mr Bonisch deliberately put an accelerant on the clothes with the intention of starting a fire.”
He said while it was possible Mr Bonisch started the fire deliberately, it may also have been accidentally started by, for example, a discarded match or cigarette which had not been properly extinguished.
Mr Bonisch was known to smoke in the room.
He said for these reasons, it was not possible to reach a conclusion “to the required standard of proof” about whether he started the fire accidentally or intentionally.
There was also uncertainty about what effect, if any, Mr Bonisch’s mental health difficulties had on his actions that evening and whether they contributed to the fire starting.
However, there was evidence that Mr Bonisch was struggling to cope in the period before his death and he had not been taking his prescribed medication.
When the fire started, it would have been possible for Mr Bonisch to escape through his door, which was unlocked.
Coroner Elliott said it was unknown what Mr Bonisch’s initial actions were when the fire started.
He may have spent some time trying to extinguish it before attempting to escape.
“It is, however, clear that Mr Bonisch inhaled toxic chemicals, including carbon monoxide.
“This would likely have caused him to lose consciousness quickly, thereby compromising his ability to escape.
“The inhalation of these products of combustion caused his death.”
Coroner Elliott said given the uncertainties in the case, there was no basis for any comments or recommendations under section 57A of the Coroners Act 2006.
