WITNESSES and dashcam footage show Paul Gerard Crimmins' car did not slow or veer as it careened across a highway in a Bells Creek crash that killed a Sunshine Coast man.
Now a jury must decide if Paul Gerard Crimmins, 59, had any warning before he is believed to have lost consciousness, swerving across a Bruce Hwy median strip and ploughing into an oncoming car.
The crash on November 27, 2015, killed 69-year-old Noosaville man Graeme Warren and severely injured his wife Dianne Warren, Mr Crimmins and his wife Gail Crimmins.
Yesterday the jury at Maroochydore District Court retired to consider whether Mr Crimmins was guilty of dangerous driving causing death and grievous bodily harm.
Defence counsel Peter O'Connor told the jury the element in dispute was whether Mr Crimmins was driving dangerously.
Mr Crimmins had told police and the court he couldn't remember the moments before the impact.
"As a matter of certainty, he doesn't know and can't know what happened," Mr O'Connor said.
Mr O'Connor told the jury in his closing address it was common for victims of a serious car crash to lose their memories surrounding the events.
Both Mrs Warren and Mrs Crimmins were unable to remember the moments leading up to the crash.
Mr O'Connor said the only reasonable explanation for Mr Crimmins' swerve was that he lost consciousness at the wheel.
He said Mr Crimmins was "awake and fully attentive" just three minutes before the crash, when he spoke to his wife at the Roys Rd overpass.
"There's no evidence, reliably, that there was any warning," Mr O'Connor said.
Crown Prosecutor Mark Whitbread supported the inference that Mr Crimmins passed out, but said there were signs before the crash he was becoming drowsy.
He told the jury dashcam footage showed the Nissan Patrol was drifting to the left of the lane and may have passed the audible lines at one point.
"It seemed that he is losing concentration," Mr Whitbread said.
Mr O'Connor said suggestions from the prosecution that Mr Crimmins may have turned up the radio and began speaking less because he was drowsy were "mere speculation".
The jury will continue deliberating today.
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