A SCOTTISH mother of four who stopped to help a motorist was killed instantaneously when she was hit by a vehicle driven by a drunk driver on a road in Canada, a trial has heard.

Charlene Reaveley, 30, and another woman died when a vehicle allegedly driven by Cory Sater, 40, careered into her and then drove off. He is accused of causing death by dangerous driving.

The first day of the trial, at the Supreme Court of British Columbia, heard Sater allegedly drank six double rye-and-cokes and two Jager Bombs before heading out in his vehicle.

The court was told Mrs Reaveley and her husband Dan had stopped to help Lorraine Cruz, 26, and her boyfriend, Paulo Calimahin, after their vehicle hit the central reservation on Lougheed Highway, near Vancouver, half an hour after midnight on February 19, 2011.

But as they stood on the roadside, a Jeep Cherokee careered into them, before driving off. The abandoned vehicle was found a few kilometres away.

Mrs Reaveley, a fitness trainer from Dundee, and Ms Cruz were thrown 65 feet and died instantaneously, while Mr Calimahin was seriously injured.

In the 911 call to emergency services, played to the court, Mrs Reaveley's friend Kimberley Moore was heard reporting Ms Cruz's accident. The court then heard Miss Moore crying out after the women were struck, then saying, "Oh, no. No, no. My girlfriend just got run over. The guy who hit them took off."

When she and her partner, Giacomo de Benedicts got closer, she asked someone if Mrs Reaveley was dead.

In the recording she is heard saying: "She's, oh God, dead.

"She's dead, no. The two girls are dead, my best friend is dead and the other girl is dead." She was then heard sobbing as sirens arrive in the background.

Both the victims' families and the accused cried as the call was played. Sater hung his head and wiped away tears.

In his opening remarks, Christopher McPherson, prosecuting, had told jurors: "A normal person, a sober driver ought to have been able to see the people on the road and the vehicle in the location where it was, facing the wrong way against traffic."

Sater pled not guilty to 10 charges, including failing to stop at the scene of an accident causing bodily harm, two counts of impaired driving causing death, impaired driving causing bodily harm, two counts of causing an accident resulting in death, causing an accident resulting in bodily harm, two counts of dangerous driving causing death and dangerous driving causing bodily harm.

Mrs Reaveley, who was seven when she emigrated from Scotland, and Dan were childhood sweethearts. They had their first son Kaeden in 2000. Four years later they had daughter Rebecca, and then Alicia in 2006 and son Tristan in 2009.

The tragedy inspired Mr Reaveley and his father-in-law to set up a charity in his wife's name to provide assistance to families with children experiencing the loss of a loved one.

The trial continues.