On that occasion, he rolled his car 100m down a bank on Otago Peninsula.
Millar told police he could remember being in Dunedin having "a few beers" but did not recall driving.
He was taken to hospital with bruising on the brain and avoided conviction by completing a defensive driving course.
Less than a year later, Millar was drinking with Sharma and others at a commercial garage in Chicago St, Alexandra.
That evening, the defendant consumed at least one "road-cone beer bong", where the cone was used as a funnel to consume the drink.
"This forces the drinker to consume a large amount of alcohol in a short period of time," a police summary said.
Hayden Crawley, who was at the gathering after recently moving to the area, accepted a ride with Millar and at 11.45pm they left.
Millar was described by witnesses as "six out of 10" on a scale of intoxication and "too drunk to drive".
Crawley queried the direction the defendant was travelling when he sped off.
They were taking "the long way home", Millar said.
The teen driver almost immediately lost control of his car, sliding through an intersection and mounting a footpath.
Without checking for damage, Millar again accelerated away, reaching speeds of up to 120km/h in a 50km/h zone.
Both passengers asked the driver to slow down as they reached the open road but he would not, the court heard.
Crawley noticed the speedometer showed Millar's Nissan was travelling at or beyond 180km/h at one stage.
The defendant turned into an asphalt area near the Alexandra Airport terminal, where he performed "donuts".
And the recklessness continued as he drove down Coates Rd.
Millar used the handbrake to try to "drift" around a right-hand bend but lost control.
The car rolled down a steep bank and came to a violent halt when it collided with a pine tree.
The roof directly above Sharma bore the brunt of the force and he sustained severe head and neck injuries, which killed him "almost immediately", Bates said.
Millar also suffered a serious head injury, and Crawley managed to climb out of the wreckage to get help.
The defendant was taken to Dunstan Hospital before being airlifted to Dunedin, where he was put in an induced coma.
A blood test taken by medical staff put Millar at nearly twice the legal limit but doctors declined police requests for an evidential sample because of the teen's precarious condition.
By the time staff acquiesced, at noon the following day, the defendant had a zero alcohol reading.
Millar was discharged after three weeks in hospital and had no recollection of the events.
He was remanded in custody and will be sentenced in April.
