Police prosecutor Chris George said it was accepted Tackney was exceeding the speed limit — at up to 70kmh in the 60kmh zone — but the defendant had ample time to see him and remain safely at the intersection until he had passed.
It was also acknowledged by police the motorcyclist had been witnessed doing about 120kmh on the motorway earlier that day.
Counsel Joe O'Neill disputed the police's speed estimate and said there was also an issue with visibility.
Walsh, he told the court in a brief opening, had an impeded view at the intersection because of a parked car on her right.
Serious crash analyst Constable Sam McGilbert said the evidence at the scene suggested Tackney had braked hard upon seeing the Toyota Corolla pull out.
There were skid marks beginning 27m from the impact site, he said, and the motorbike — which was unregistered and unwarranted — fell to its right, sliding along the road.
Damage to the front right side of Walsh's car indicated a glancing blow which was not of sufficient force to deploy the car's airbags, Const McGilbert said.
"It was a ricochet."
However, the contact was fatal for Tackney.
The witness identified a black smudge above the Toyota's front-right wheel where he believed the motorcyclist's helmet had struck it.
The court heard the victim died of a ruptured aorta but also sustained other injuries which could have ultimately been fatal.
Brighton Rd resident Emma Hannah said she heard a "bang" but initially did not think it was a crash.
"I did not hear any braking or screeching of tyres," she said in a statement that was read in court.
Hannah said she saw a woman get out of a silver car and crouch by a motionless man on the ground.
She rushed to help.
The woman immediately began CPR, went to check for a pulse but found Tackney's wrists too "smashed up".
Instead she lifted his hoodie and looked at his chest to see if he was breathing.
Her subsequent resuscitation attempts were in vain and the man was pronounced dead at the scene at 1.30pm.
Hannah said she spoke to a friend of Tackney's by the road who was "mortified and could barely talk" before she went to the side of Walsh.
"I didn't see him, I didn't see him," she allegedly repeated.
Walsh was breathalysed and gave a negative result. She was then interviewed by another officer.
She had been going shopping at the time, she said, and by the time she saw the motorcycle it was too late to act.
At the start of yesterday's judge-alone trial, before Judge David Robinson, there was a suggestion that the bike did not have its headlight activated.
But that position was promptly abandoned by the defence after experienced motorcycle service manager Dennis Landrebe gave evidence that all late-model Harleys had permanent automatic headlight operation.
Const McGilbert said the road at the time of the collision was dry and visibility was good, leading him to the conclusion that Walsh did not check the way was clear.
The court will today hear from the pathologist who completed the postmortem and the police officer in charge of the case.
The defence will call its own serious crash expert, it has confirmed.