The 19-year-old had collected three traffic infringement notices within nine months of becoming a probationary driver and had admitted to a friend drink-driving ''all the time''.

Just after midnight in Mill Park on January 17, 2010, he was drunk and angry, speeding in his car overloaded with five passengers, ignoring red lights and talking on a mobile phone.

The Victorian Coroners Court yesterday heard police found Johnstone's car was travelling at 150 kilometres an hour when he lost control before it crashed into a large tree with such ferocity it snapped it from the ground.

Killed instantly was Johnstone, his brother William Te-Whare, 15, and backseat passengers Benjamin Hall, 19, Matthew Lister, 17, and Anthony Iannetta, 18.

The sole survivor was Mr Iannetta's sister Elissa, 15.

Detective Leading Senior Constable Shane Miles described Johnstone as a ''loose cannon'', his conduct as ''deplorable'' and the passengers as ''hanging on for dear life''.

Johnstone was solely responsible, he said, and had taken the lives of others in his hands without ''respect for the law''.

He had drunk most of 24 Vodka Cruisers that night and later collected his four passengers after an altercation with a group he was bent on seeking revenge against.

While Mr Lister and the Iannettas wanted to go home, they remained in the car while the other two were ''easily coerced'' to go with him.

Witnesses described the car's engine as ''screaming'' and passing at a speed ''nothing I have ever seen on a legal road''.

Detective Miles noted that Johnstone's licence ''most likely'' would have been suspended at the time but for an error in the system that records infringement notices.

Coroner Heather Spooner distinguished Johnstone's ''high risk-taking'' from young drivers over represented in crashes and said she was focused on safety issues and programs than the now-corrected records' error.

Antonietta Cavallo, a VicRoads' manager for road user behaviour, said in evidence that Johnstone's behaviour indicated he was ''impervious or immune to positive influences'', the regulatory licence system and police action.

Ms Cavallo said an analysis of him and the crash circumstances fitted the profile of a small group of drivers who take ''extreme risks over sustained periods''.

She told Ms Spooner recent overseas safety-related developments such as speed-limiting devices and alcohol sensors were long-term hopes.

Ms Spooner will deliver her findings next month.