A truck driver can't be found guilty of dangerous driving causing death because there is no proof that he didn't blackout at the wheel before the crash, his lawyer says.
Kenneth Laurence Pillar, 55, claims he had a coughing fit and passed out when his cement-loaded semi-trailer veered on to the wrong side of the road on a narrow bridge in June 2015.
The truck crashed into an oncoming car, killing 61-year-old school teacher Maria Dowdell, and Pillar is on trial for causing her death.
Prosecutors say he was distracted by what his girlfriend was doing in the cabin and the pair later lied to police about what happened to avoid responsibility, making up the story of the blackout.
But Pillar's lawyer says a jury can't rule out a blackout as a reasonable explanation for the crash, even though the medical cause of it has puzzled doctors.
"From the outset we can't exclude that Mr Pillar did not blackout," defence lawyer Nicholas Healy told the Supreme Court in his closing remarks on Monday.
"I can't tell you what the cause of his blackout was. The doctors couldn't tell you.
"But if you can't exclude that as a reasonable possibility, then the Crown can't prove (his guilt) beyond reasonable doubt.
"The onus is on the Crown. Not Mr Pillar."
As if on cue, Pillar coughed and spluttered in the dock before his eyes closed and his head rolled back. He was out.
It caused some supporters of the victim who were present in court to quietly groan.
Throughout the trial, the courtroom has been forced to pause whenever Pillar blacked out in the same way, usually for about 20 seconds at a time.
Doctors found no physical reason for Pillar to suffer blackouts but said they they could be "psychogenic", meaning caused by psychological causes.
"Not one doctor told you that Mr Pillar's blackouts were not genuine," Mr Healy said.
The court previously heard the truck was travelling about 95km/h when it crashed and did not brake before it collided with Ms Dowdell's car.
Mr Healy said Pillar was an experienced truck driver and if he were conscious, he would have braked or reacted if he was being distracted in the cabin.
Judge Sophie David will deliver her summary of the trial on Tuesday before the jury is sent out to deliberate on a verdict.