South Australia’s Police Commissioner and his wife have tearfully told a court of the gut-wrenching devastation at losing their youngest son in a crash last year.

“Charlie was a vibrant, caring, fun-loving, generous young man with a love of life and plans for the future,” they told the District Court in a statement that Commissioner Grant Stevens read aloud as his wife stood by his side.

“He loved his family and his mates, and we all loved him being a part of our lives.

“Now all we have are memories of him, and that is not enough.”

Dhirren Randhawa, 19, pleaded guilty to a charge of aggravated driving without due care and leaving the scene of a crash at an earlier hearing.

The more serious charge of causing death by dangerous driving, and a charge of failing to truly answer questions, were dropped.

Grant Stevens and his wife Emma delivered a victim impact statement in the District Court on Thursday. (ABC News: Lincoln Rothall)

Charlie’s parents said they could not accurately describe their loss, and Randhawa could “not possibly understand what you have taken from us”.

“Your actions that night in November last year have changed us and our family forever,” they said.

They said losing Charlie just as he reached adulthood had “taken so much of the colour out of our lives”.

Mr Stevens’s voice faltered as he described how it took all the couple’s effort just to get through what would have been Charlie’s 19th birthday in April this year.

“We know that that grief is with us for the rest of our lives,” he said.

“Not a single day goes by that we don’t think about Charlie … there’s not a day where we don’t shed a tear thinking about our son and how much we miss him.”

Mr Stevens said recalling saying goodbye to Charlie in hospital “broke our hearts”, while seeing their other children suffering at the loss of their brother “hurts just as deeply”.

He said he also sees the pain in Charlie’s friends, who still visit, “particularly the ones who were there that night when you left him on the middle of the road”.

They said his bedroom – which they had described as messy but perfect in a public letter last year – would remain the same because they could not bring themselves to change it “and we don’t want to”. 

Charlie Stevens was described as “kind, inclusive of all and a pillar of strength”. (Supplied: SA Police)

They acknowledged that it must have been difficult for Randhawa, who had taken responsibility for his actions, too but told him “you get to move on”.

“We want you to remember Charlie and what your actions have denied him and us,” they said.

Charlie’s older sister, Sophie Tregloan, recalled how she froze when she arrived at Flinders Medical Centre, where the family were told Charlie had suffered an irreversible brain injury and would not survive.

She said Randhawa had taken “the little brother everyone wanted” from her family in a “split-second dumb decision”.

“He was a brilliant painter and drawer, he was a master of the egg and bacon sandwich – but it’s Charlie’s heart that I will miss the most,” she said.

“He was kind, inclusive of all and a pillar of strength.”

“Do I hate you? Yes, I absolutely do – but what I hate the most is what you have done and taken from my family.”

Randhawa read aloud a letter of apology, telling the court he was sorry for his crimes and that Charlie’s death was “constantly in my thoughts”.

“There’s so much I’d like to say, but mostly I want to say I’m sorry and I’m sorry to Charlie,” he said.

His mother, Amreeta Stara, also told the court of her sorrow, condolences and regret for the “devastating incident”, which had also affected her family – who had received death threats in the wake of the crash.

Dhirren Randhawa (centre) told the court that Charlie’s death was “constantly in my thoughts”. (ABC News: Lincoln Rothall )

Jane Abbey KC, for Randhawa, told the court her client’s remorse was genuine and asked the court to take that, his youth, lack of criminogenic factors and lack of any prior offending into account when imposing a sentence.

She said it was accepted Randhawa should have been keeping a better lookout when he struck Charlie and told the court he drove away from the scene in “shock and disbelief” before stopping and calling his mother to ask what he should do.

She said he then drove toward Victor Harbor and stopped when he saw a police car, to tell them what had happened.

She urged the court to suspend any term of imprisonment imposed, and said he was at risk of deportation if he was jailed.

Prosecutor Martin Hinton KC told the court a sentence of imprisonment should be imposed due to factors including the gravity of the offending and said the question of suspension would be a fine balance for the court to determine.

He said the circumstances of the crash involved Randhawa “accelerating toward Charlie Stevens and his friends, knowing that they were on, or had just been on, the roadway”.

Mr Hinton told the court Randhawa had not exceeded the speed limit, but that he had accelerated toward them.

Emma and Grant Stevens said they could not accurately describe their loss. (ABC: Lincoln Rothall)

He said Randhawa should have made an “effort to minimise the risk”, and should have immediately stopped to “give all possible assistance” in accordance with moral and legal obligations and community expectations.

“This is a unique case, it’s unique in that the death of Charlie Stevens has touched the community broadly, grief has been expressed widely and deeply,” he said.

“The commissioner’s son, through all the might and power that the commissioner has, could not be protected. That touched us all.”

Randhawa will be sentenced later this month.