Matthew McMahon’s obsession with purple led to Mitchell St hostel car fire

A Darwin father set a stranger’s ute on fire after being haunted by creatures from the Harry Potter series. See how the court system is trying to set him on the right path.

On Thursday, Matthew McMahon was sentenced to two years in prison by Acting Justice Trevor Riley after pleading guilty to using fire to cause damage. He suffered from delusions about slavers, paedophiles, incestors, death-eaters and rapists.

A Darwin man obsessed with the colour purple and haunted by visions of death-eaters, slavers, paedophiles and rapists set a stranger’s ute on fire.

A psychiatrist has explained to the Supreme Court in Darwin the state of a 47-year-old father’s paranoia when he poured fuel over a tourist’s Nissan ute in October 2021.

On Thursday, Matthew McMahon was sentenced to two years in prison by Acting Justice Trevor Riley after pleading guilty to using fire to cause damage.

A Mitchell St hostel duty manager heard reports of a guest threatening others, swearing and playing loud music just before midnight on October 18 2021.

The court heard McMahon was intoxicated by a mix of 24 cans of full-strength beer and the fumes of a butane canister.

As he was escorted out, McMahon called out: “You could burn this place to the ground from 5 metres with a Zippo lighter”.

Three hours later the Darwin father watched as flames consumed a ute left in a nearby carpark.

The court heard McMahon threw flammable liquid on the bonnet of a Nissan Utility with West Australian plates before setting it alight, causing $2500 in damage.

The hostel manager told the court he had “nightmares” from the night, and suffered from post-traumatic stress disorder.

Consultant psychiatrist Dr Lester Walton said the 47-year-old had a schizoaffective disorder and suffered from paranoid delusions.

Acting Justice Trevor Riley

The court heard that at the time McMahon was “obsessed with the colour purple” and for reasons he could not explain associated it with “violent thoughts about spiders”.

“Spiders is an acronym you use for ‘slavers, paedophiles, incestors, death-eaters and rapists’,” Justice Riley said.

Death-eaters are creatures from Harry Potter.

McMahon told his psychiatrist he had been “disrespected by people wearing purple shirts” at the hostel, and had targeted the ute as it looked purple.

He had also told a psychiatric registrar he had telepathic powers and there were chips in his brain.

Despite a “disturbing history” as a victim of abuse, the court heard McMahon had no professional assistance and had suffered from psychosis.

The court heard that the 47-year-old was responding to treatment and regular medication.

“You said the voices inside your head had subsided,” Justice Riley said.

“This offending was obviously serious, although it must be considered in light of the state of your mental health at the time”.

On Thursday October 20, Justice Riley sentenced McMahon to two years in prison, with one year already served.

His sentence was suspended, with the 47-year-old to move to Banyan House residential recovery program and remain under community supervision for two years.

However, both McMahon’s mother and Dr Walton were concerned that the mentally-troubled man would be criminalised if he had another breakdown.

“Your mother … expressed concern at what she thought was a lack of resources available for people in mental distress in Darwin,” Justice Riley said.

Dr Walton said breaches of his community order should be treated by “hospitalisation rather than a return to prison”.

Originally published as Matthew McMahon’s obsession with purple led to Mitchell St hostel car fire