The crash killed Mr Smith-Brown, while his passenger and heavily pregnant girlfriend was rushed to hospital. Motorists uninvolved in the chase were badly injured.

An inquest into Mr Smith-Brown's death began in the ACT Coroner's Court on Monday, and will examine the lead-up to the crash and ACT Policing's pursuit policies.

At about 5.45pm on the day of the pursuit, a police car equipped with automatic number plate recognition technology picked up on a maroon Mitsubishi Magna passing in the opposite direction, the inquest heard. The technology alerted officers the car may have been unregistered and its driver may have been unlicensed.

A video from inside the police car and played at the inquest showed the police car perform a u-turn, and turn left onto Drakeford Drive, where it pursued the Mitsubishi north, its lights and sirens on, weaving in and out of light traffic.

A radio operator could be heard instructing police to terminate the pursuit, and moments later the Mitsubishi crashed where Boddington Crescent intersected with the major arterial road.

Mr Smith-Brown, who was not wearing a seatbelt, suffered serious head and internal injuries and died at the scene. His girlfriend, Felicity Jessop, was injured and taken to hospital, where she gave birth to a son she named Tim.

In an at-times hesitant testimony, Ms Jessop told the inquest Mr Smith-Brown drove through three red lights, and she had seen on the speedometer they were travelling at about 200km/h.

She said she began to feel scared, and told him to slow down.

Ms Jessop agreed under questioning by counsel assisting the Coroner, Ken Archer, that Mr Smith-Brown had accelerated to put distance between himself and the police.

She said the police car had been at times within metres of them and it wouldn't "back off", adding that police should have stopped the pursuit after the first red light.

In the moments before the crash, she told the inquest she had seen the police car slam its brakes. Earlier, she had said "our brakes weren't that good".

The inquest heard Mr Smith-Brown was an unlicensed driver – though he was eligible to apply for a license – and the Mitsubishi was unregistered although its plates belonged to another car, also unregistered.

Ms Jessop said while they had not spoken during the pursuit – except when she told him to slow down – Mr Smith-Brown knew the Mitsubishi's plates were false.

In tests on Mr Smith-Brown's blood following his death, police found trace amounts of cannabis and methamphetamine in his system, lead crash investigator Sergeant Tracey Duck told the inquest.

He also had on him a small amount of the drug ice.

ACT Policing's pursuit policies were under review at the time of the Mr Smith-Brown's death, and have since changed.

The inquest heard a committee regularly reviewed police pursuits. Sergeant Duck agreed under questioning by Darryl Perkins, who represented the family of Mr Smith-Brown, there were no civilian or non-AFP members on the committee.

The hearing continues before Coroner Peter Morrison.