Here's How They Catch A Bushfire Arsonist
A 79-year-old man from South Australia has been arrested over the weekend and charged with four counts of causing a bushfire.
He is far from the first -- in the last two months, NSW Police have charged 24 people over alleged deliberately-lit bushfires. And we have many months left to go in the season.
It’s an unfortunate fact that about 13 percent of bushfires are caused by arson and 37 percent are labelled "suspicious", with the strength and intensity of fires exacerbated by fire-prone conditions brought about largely by climate change.
How do investigators know a fire is deliberately lit? And what can be done to identify offenders?
Firestarters Are Rarely Punished. Here's What Could Happen Instead.
Bush fire arson is a notoriously easy offence to commit and a notoriously difficult one to detect let alone prosecute. Experts say it's time police and government rapidly change their approach when it comes to stopping it.
The process of investigating a bushfire is a collaborative effort involving fire crews, specialist investigators and law enforcement.
“It’s a crossbreed of skill sets,” notes Richard Woods, fire investigator at Wildfire Investigations and Analysis, and Adjunct Associate Lecturer at Charles Sturt University.
“The first crews generally to attend are the fire service, having officers who have experience in identifying a more obvious cause, however if there is a need, they may require the expertise of a specialist fire investigator.”
In particular, if suspicions are raised that a bushfire may have been deliberately lit, most jurisdictions across Australia will also have specialist Forensic Police units attend.
Procedurally, the process of fire investigation involves tracing a blaze to its origin, collecting evidence at the scene and gathering information to determine cause.
Reading The Flames
Fire is a chaotic chemical reaction impacted by fuel, topography and weather. However, there are ways to read the behaviour of bushfires to determine its origin.
“Finding the origin of a bushfire is based on an internationally recognised and accepted method," notes Wood.
“It essentially involves interpreting the burnt remains at a fire scene and tracing the movement of the fire backwards.
“Every time a bushfire moves through an area it will leave a distinctive pattern.”
A bushfire which has multiple points of ignition suggests deliberate lighting as does evidence of a series of suspicious fires being lit in the same area.
Determining the origin of a bushfire will occur even when arson isn’t suspected, as it assists in preventing future blazes. Only by knowing the cause of fires (man-made or otherwise) can you do something to prevent them.
Identifying The Cause
The investigation of the fire scene is a meticulous process and is examined by investigators who have the training and experience to know what to look for.
“Evidence could be anything from discarded matches, a piece of catalytic converter from a vehicle, a downed power line and after storm activity, the remains of a lightning struck tree,” notes Woods
In bushfires, the origin is the coolest part of the fire, as this is where it ‘establishes itself’, even when the resulting bushfire is of high intensity. This often means evidence of an ignition source remains at the origin.
Where multiple origins are found, investigators will try to determine if there were two separate sources of ignition or if the second fire is a result of spotting from existing fires.
Evidence found at the scene can also help in identifying the offender.
Andrew Robert Briggs was convicted of lighting four fires near the township of Great Western in Victoria as part of a revenge plot in 2016, after one of the crime scene investigators found a receipt from IGA under his name.
Like any criminal investigation, multiple sources of information will be gathered in order to identify an offender.
Mark Ganon, who pleaded guilty to setting a number of fires in 2017, was discovered after police consulted CCTV footage showing his vehicle leaving the scene of a blaze.
Eye witnesses are often the key to an investigation, placing an offender at the scene during the time of ignition.
“The assistance of the public is vital,” said Woods. “My message is not to hesitate in providing information to police and fire service officers if you have information, no matter how minor you consider it to be.”
Authorities are encouraging members of the public to record the details of suspicious vehicles and note the appearance of anyone acting suspiciously near fires. Any suspicious behaviour can be reported to Crime Stoppers on 1800 333 000.