SA police commissioner's family face teenage driver who killed their son in court

South Australian police commissioner Grant Stevens and his family have confronted in court the driver who killed their youngest son in a hit-run crash.

Family and friends surrounded Stevens and his wife Emma as they told Dhirren Singh Randhawa he would never comprehend the pain he caused in the crash last November.

"You cannot possibly understand what you've taken from us," they said.

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"Losing Charlie just as he was becoming a man we were immensely proud of has taken so much of the colour out of our lives.

"His room is still the same and it always will be.

"We can't bring ourselves to change it and we don't want to."

Charlie's sister Sophie told the driver she hates him.

Randhawa, 19, pleaded guilty in June to one charge of aggravated driving without due care and leaving the scene of a crash that caused a death, at Goolwa Beach, south of Adelaide.

Charlie, 18, was celebrating at Schoolies when Randhawa hit him.

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Randhawa has previously apologised to the family in a letter.

Today, he did so publicly in the pre-sentence hearing.

Randhawa told the Stevens family he thinks about them every day and that hearing Charlie's life support had been switched off was the worst moment of his life. 

New details about the incident were heard for the first time, including that while Randhawa wasn't speeding, he did accelerate towards Charlie and his friends.

The consequences for Randhawa are also far-reaching.

He has received death threats, including one that needed police involvement, and faces possible jail time.

He could also be deported to Malaysia.