The US-Somali cop accused of fatally shooting an Australian woman outside her home had brandished his gun on a driver during a traffic stop months earlier, it has been revealed.

Dashcam footage has emerged showing former Minneapolis police officer Mohamed Noor, 33, pointing his weapon at a driver after he had stopped him for allegedly not using his turn signal in May 2017.

Noor has been charged with second-degree intentional murder, third-degree murder and second-degree manslaughter for allegedly gunning down life coach Justine Ruszczyk Damond, 40, after she called 911 to report a possible sexual assault behind her home in July 2017.

Dashcam footage has emerged showing former Minneapolis police officer Mohamed Noor (left) 33, pointing his weapon at a driver after he had stopped him for allegedly not using his turn signal in May 2017

Noor's trial is expected to begin April 1. He has been charged with second-degree intentional murder, third-degree murder and second-degree manslaughter for allegedly gunning down Australian life coach Justine Ruszczyk Damond (right) 40, when she ran out of her home in pyjamas to meet officers after calling 911

Ms Damond, who was originally from Sydney, rushed outside in her pyjamas to meet officers when Noor opened fire.

Prosecutors say the video provides evidence that Damond's death was not a justifiable accident claiming Noor had a history of 'unnecessarily escalating force,' KARE11 reported.

However, Noor's defence team has argued the clip is misleading and say the gun was pointing down between the officer and the driver. Defence lawyers are now fighting to keep the video out of the trial.

Court documents filed in advance of Friday's hearing provide an indication of issues that are expected to come up.

Among them, prosecutors want to use Noor's pretrial silence against him, and they want to submit evidence from a pre-employment psychological evaluation conducted in 2015.

The defence wants to keep such evidence out, and wants to sever the most serious murder charge from the other two counts.

It's not clear when Judge Kathryn Quaintance will rule.

Noor's trial begins April 1. He has not entered a formal plea, but court documents indicate he'll plead not guilty and will claim he was defending himself and others on the night of the shooting.

Noor has not spoken with investigators. His partner that night, Matthew Harrity, told investigators he was startled by a loud noise right before Ms Damond approached the driver's-side window of their police SUV.

Damond, who was originally from Sydney, had called 911 to report a possible sexual assault behind her home in July 2017. Prosecutors have argued her death is not a justifiable accident

Noor was sitting in the passenger seat when he fired past his partner, who was behind the wheel, as Ms Damond approached the driver-side window. Pictured above is the crime scene

According to the criminal complaint, Harrity, who was driving, heard a voice and a thump and caught a glimpse of a person's head and shoulders outside his window.

He then heard a sound like a lightbulb breaking, saw a flash and looked to his right to see Noor in the passenger seat with his arm extended.

He looked out his window and saw Ms Damond with a gunshot wound.

Prosecutors say investigators asked to arrange for a voluntary interview with Noor and that he declined through his attorney.

Defence attorneys say prosecutors aren't allowed to use that against Noor in court because he has a constitutional right not to make any self-incriminating statements.

But prosecutors argue that they can use a defendant's pre-arrest silence if the defendant was under no government-imposed compulsion to speak.

'In sum, the defendant had a choice on whether to tell his side of the story during a voluntary interview in a non-coercive setting,' prosecutor Amy Sweasy wrote.

'His decision not to do so is relevant.'

Prosecutors also want to submit evidence from a pre-employment psychological evaluation, including a standardized psychological test that assesses personality traits and psychopathology.

The test found that Noor was disinterested in interacting with others and, when compared with other officers, was more likely to be impatient or have difficulty confronting people.

Noor (pictured leaving court in September) has not entered a formal plea, but court documents indicate he'll plead not guilty and will claim he was defending himself and others on the night of the shooting

Noor's defence team has argued the clip is misleading and say the gun was pointing down between the officer and the driver

A psychiatrist concluded that overall, Noor was fit to be a police officer, saying the test results don't carry much weight.

Prosecutors say the test results are admissible as character evidence, and they matter because the jury has to decide whether Noor acted as a reasonable police officer would act.

The defence says prosecutors don't want to admit the overall psychological evaluation, which found Noor fit for duty, but instead are pointing to a test that is 'unsupported speculation.'

Prosecutors also want to allow jurors to hear about some prior acts by Noor while he was a police officer, including an incident in which he unholstered his gun during a traffic stop just two months before Ms Damond was shot. Defense attorneys oppose this.

It's unknown whether Noor, who is Somali-American, will testify at his trial.

In one of the pretrial filings, prosecutors say they want statements that Noor made to defence investigators and experts to be kept out of the trial - unless Noor testifies first.

Prosecutors say they otherwise would have no way to challenge what they say are 'textbook self-serving statements.'

Defence attorneys are also seeking to omit other evidence. And they are asking that, prior to jury selection, potential jurors be shown a video about unconscious bias, with the goal of helping jurors recognize potential biases. The state opposes this request.