SA man found guilty of road crash murders

A South Australian man has been found guilty of two counts of murder over deliberately driving his car into the path of an oncoming vehicle in 2014.

A Supreme Court jury on Monday found Michael Frank Knowles guilty of the murder of James Moore and Natasha Turnbull in the crash on the Lincoln Highway near Middleback in December 2014.

Knowles had offered to plead guilty to two counts of causing death by dangerous driving but his pleas were rejected by prosecutors.

At the opening of his trial last week the court was told Knowles had set out to kill himself when he drove his Nissan Patrol into the path of Mr Moore's Mitsubishi Pajero.

Mr Moore, Ms Turnbull and two other friends, Jason Bristow and Amy Jones, had been returning to Whyalla from Coffin Bay after spending a day at the beach.

Ms Jones and Mr Bristow suffered injuries in the crash.

Prosecutor Mark Norman said Knowles must have known that driving his car into the other vehicle with sufficient force to kill himself would probably kill or cause serious harm to anyone in the other car.

"But despite that knowledge, and instead of choosing to drive into a tree or a rock or a brick wall or even an empty parked car, he chose to drive straight into James Moore's Pajero," the prosecutor said.

Knowles admitted causing the crash and being drunk, but disputed prosecution allegations that he was trying to take his own life.

* For support and information about suicide prevention, call Lifeline on 13 11 14 or Suicide Call Back Service on 1300 659 467.