Miss Hastie was driving down Southampton St, heading east toward Havelock North, when she approached the intersection with Railway Rd on October 6 last year.
Sergeant Kristina Eckhold was parked on the forecourt of the BP station watching for "red-light runners" because it was known as a troublesome intersection.
Just after 9am, she said, she watched Miss Hastie "blatantly" drive through a red light. She radioed Constable Grant Marshall, who was parked further up the road, to pull the car over.
The court heard that Miss Hastie had just dropped her son off at daycare and was heading home to nurse a bad ear infection.
She insisted the light was amber, so Mr Marshall used his discretion and gave a ticket for failing to stop for amber instead of failing to stop for red.
Miss Hastie maintained that "she wouldn't be sitting here" if she didn't believe in her own innocence.
She said she was surprised how quickly the light turned red.
Senior Constable Cory Ubels carried out a "time and distance analysis" to determine if there was any validity in Miss Hastie's claim that there was insufficient time for her car to cross the intersection before it turned red.
The traffic signals are set at a maximum of 30 seconds for green, three for amber and a further two seconds for the red signal, before the traffic along Railway Rd is given the green light.
At a constant speed range of between 30km/h and 50km/h and using the distance of the intersection of 24.9 metres, it would have taken between 1.77 and 2.9 seconds for her car to clear the intersection.
There was no way Miss Hastie would have seen the lights turn red if she had been crossing the limit line as it changed to amber, Mr Ubels said. Her car must have still been approaching the intersection when the lights turned amber and she would have had sufficient time to stop, he said.
After receiving the infringement notice, Miss Hastie did her own research and found that the time lights stayed amber differed from three seconds to 4.4 seconds.
She wanted to know how an average citizen could make an informed decision about whether to stop if they did not know how long an amber light would remain before turning red.
"People aren't aware ... it's so different between intersections, that's why I feel I'm not guilty."
However, Justices of the Peace Alison Thomson and Andrew Renton-Green found the charge proved. Miss Hastie was fined $150 and ordered to pay $30 court costs.
While most people would just pay the fine, she told Hawke's Bay Today she had no regrets about taking the matter to court.
"With such a variety of yellow-light times it's no wonder that 'operation red-light runners' is held at an intersection with a 3-second time compared with the 4.5-second intersection just up the road."
She would like to see a national standard for how long lights must remain amber.
A New Zealand Transport Agency spokesman said legally lights must remain amber for three seconds at least.
However, that could be increased for larger or complicated intersections. A typical amber light in an urban area lasts for approximately four seconds.
A Ministry of Transport spokeswoman said the Government sees no need to further legislate for a standard time for all intersections.
"It is irrelevant how long the yellow light stays on.
"The key issue is for motorists to stop if they safely can."
The timing of amber lights was best left to the relevant road controlling authority in charge of the traffic lights, as they could take into account the prevailing speed limit and the characteristics of the intersection, she said.