A magistrate's decision to drop charges against a diabetic driver who was in the midst of a medical episode when his SUV crashed into a crowd, killing five, has left the victims' families in shock.
William Swale's doctors and legal team convinced a magistrate at a committal hearing held in Ballarat on Thursday there wasn't sufficient evidence to find him guilty of any of the charges because he had not been capable of making a conscious decision to drive, as he was in the grips of a hypoglycaemic attack at the time.
Mr Swale had been charged with five counts of culpable driving causing death, two counts of negligently causing serious injury, and seven counts of reckless conduct endangering life, following the November 2023 tragedy outside a pub in Daylesford, in Central Victoria.
Mr Swale is now clear of all charges, but prosecutors could still bring him back before the courts.
Footage of him driving slowly in the lead-up to the crash showed bizarre behaviour, which could be explained by a hypoglycaemic episode, or a "hypo", as diabetics call it.
How common are hypoglycaemic episodes?
Endocrinologist Ricky Arenson specialises in diabetes care.
While he could not comment on the Daylesford case specifically, he said that generally speaking, diabetics were safe on the roads.
Dr Ricky Arenson is a Victorian endocrinologist. (Supplied: Ricky Arenson)
He said it was not uncommon for people to experience hypoglycaemic episodes, but it was uncommon to lose total cognitive awareness.
"You don't often hear of people passing out and crashing their cars with diabetes, so I don't think it's something we should alarm the public about," Dr Arenson said.
"It's actually an uncommon problem and, as both patients and doctors and diabetic educators, we do a lot of work to ensure that diabetics are safe on the road.
"On the whole, given that you haven't encountered this problem very often, it shows that mostly that is the case."
What's a hypo?
Hypoglycaemic episodes mostly occur in diabetics when their blood sugar levels become too low.
Dr Arenson told the ABC that hypoglycaemic episodes where diabetics were unaware they were having an attack, or lost total cognitive control, were rare.
Mount Macedon man William Swale leaves the Ballarat Magistrates' Court with his wife, Thea, and daughter Georgia. (ABC News: Billy Draper)
"So, generally speaking, before people start to become confused, they experience things like shaky hands, headache, fast heartbeats, they feel restless," Dr Arenson said.
"They don't feel great and then that often progresses into irritable mood, confusion, and the inability to think straight.
"Ultimately, if sugars keep dropping, people can actually lose consciousness altogether; they can have seizures and they can even die."
It is the opposite of a hyperglycaemic episode, which occurs when blood sugar levels are too high, and is less common.
What happens during a 'hypo' episode?
Keryl Paxinos has lived with type 1 diabetes for 50 years.
In that time, treatments and available technology have progressed.
But hearing about the Daylesford crash brought on feelings of deep sadness. She believed many of her fellow diabetes sufferers would have felt it too.
Keryl Paxinos was diagnosed with type 1 diabetes as a teenager. (Supplied: Keryl Paxinos)
"I was so upset when I heard that; it's a horrendous tragedy," Ms Paxinos said.
"I was upset for the people who were victims in that crash, but also for the man himself. He must have felt absolutely terrible.
"I mean, it's no different from anyone having a heart attack or some other sort of medical episode."
All diagnosed insulin-reliant diabetics, like Ms Paxinos, require regular reviews with their doctor. The results are relayed to VicRoads, which then decides whether the person is fit to drive.
Ms Paxinos has a blood glucose monitor and is alerted if her blood sugar levels are too low.
But she doesn't always know if she's suffering a severe "hypo".
It is usually her loved ones who notice she is looking pale and vacant.
"You lose insight into how unwell you're becoming," Ms Paxinos said.
"You start to get quite cold and clammy and your body is basically just shutting down.
"You start to lose coordination if you're having severe hypo; you almost can't process with your eyes what you're seeing."
Do people know when they're having one?
Yes, most of the time. But Dr Arenson told the ABC: "It depends."
If diabetics often experience low blood sugar levels, they are less likely to have any warning.
In rare cases, diabetics can experience symptoms similar to that of drug or alcohol impairment and have little to no insight.
"That's because the brain is the most glucose-dependent organ in the body," Dr Arenson said.
"Most people will get warning symptoms before they reach the point that they are significantly cognitively impaired or confused, although people might ignore some of those symptoms, particularly if they're distracted.
"So if someone's getting a bit irritable and getting slightly shaky hands or something like that, they may not necessarily always notice that.
"Once hypoglycaemia gets worse, it is quite common for people to lose judgement, to become mentally confused and certainly be quite cognitively impaired, which you could compare to drunkenness."