A P-plate ute driver who called himself the "drift king" thought "he was invincible" but "failed to a gross degree" to keep his passengers safe after one of them, his girlfriend, died following his collision with a tree, a prosecutor has argued.
An ACT Supreme Court trial has heard that in the early hours of October 31 in 2020, Ameen Hamdan was driving a Nissan Navara that carried his girlfriend, 16-year-old Alexis Saaghy, in the front-passenger seat and two friends in the back seats.
Hamdan, 18 at the time, was driving along Longmore Crescent in Wanniassa in wet conditions as the group spent the night socialising.
Prosecutors allege that Hamdan, who was not intoxicated, was speeding at 81km/h-100km/h in the 50km/h zone when the car began sliding on a left-hand bend before the vehicle collided with a tree.
All four occupants were injured with Alexis sustaining severe head trauma, including a fractured skull, and internal injuries.
She was taken to the Canberra Hospital where she died three days later.
Hamdan's trial began on Monday after he pleaded not guilty to culpable driving causing death and culpable driving causing grievous bodily harm.
Crown prosecutor Soraya Saikal-Skea in her closing address on Friday said that while complex scientific evidence had been presented, it "ultimately was a common-sense case".
"The accused knew his vehicle could lose grip with the road because he had just been drifting it intentionally," she said.
"We say speeding is one thing, but speeding in the rain in the dark is another."
Ms Saikal-Skea said Hamdan "failed unjustifiably and to a gross degree to observe the standard of care that a reasonable person would have observed".
"The accused owed it to the young people who were his passengers," she said.
"He owed it to Alexis Saaghy to keep her safe. He failed utterly."
In relation to a video recorded by Alexis inside the vehicle in which the song Tokyo Drift played while Hamdan called himself the "drift king", Ms Saikal-Skea said that comment showed he had been drifting.
"He thought he was invincible," she said.
The court heard that the calculated speed of the vehicle in that short video, recorded about 1.2km from the collision site, was about 32km/h covering 125m.
The prosecutor also cited the two back-seat passengers' evidence.
One was Zyad Dandash, also 18 at the time, who said that before the video, which was played to the court, the accused was not abiding by the speeding signs.
"I told him to stop and relax a bit because I didn't want him to get into trouble," Mr Dandash said.
Saikal-Skea defended the prosecutions' collision expert, senior constable James McCue, saying that while he did not attend the scene, it was to avoid apprehended bias.
She criticised the defence expert, Nigel McDonald, for not reading the data that formed the basis of the police investigation.
"We say that fact alone raises a red flag about reliability," Ms Saikal-Skea said.
Mr McDonald calculated the speed at the point of impact with the tree to be 35km/h-41km/h.
Working back from there, he determined the Navara was travelling no less than 49km/h at the start of "the observed tyre marks".
Ms Saikal-Skea said one of Mr McDonald's calculations of speed "was nothing more than an educated guess" because it was derived from only visual comparisons and not from measurements of the vehicle in question.
Defence lawyer John Purnell SC in his closing said the argument about the video showing Hamdan drifting was "impossible to hold" and one that "is wrong, totally wrong".
Mr Purnell said that before the collision, Hamdan yelled "f---" and that Mr Dandash said he thought he saw a kangaroo.
"Unless you exclude the reasonable possibility of there being a kangaroo ... you can't convict," he said.
Mr Purnell said Mr McDonald's visual-only method that related to the vehicle damage was "an accepted method for an expert to form an opinion upon".
"Despite all the cross examination about that, nothing changed. He still stuck with his views."
The defence lawyer reminded the jury about the "rubbish" calculated speeds - being between 245km/h and 367km/h, or potentially a "sonic boom jet" - related to a Longmore Crescent resident's evidence about hearing the vehicle.
"The Crown can't prove any irresponsible driving from when the video was recorded until the collision site," Mr Purnell said.
The jury is set to continue deliberations on Monday.
