The Cummings family have been vocal in their criticism of an undersized stop sign at the site, which was identified in a report before the council just days after the incident.
It took more than two years for the sign to be replaced with one of the recommended size.
The teenage ute driver, with whom Jayde was travelling, ploughed through an intersection on the rural road and straight into the path of another vehicle.
He pleaded guilty to two charges of careless driving causing death and in March this year was discharged in the Dunedin Youth Court, all note of the offence wiped from his record.
Judge Dominic Flatley ordered the family of the victims be informed of the result but the message was never given to Cummings.
"We need to do a lot better by people in your situation than we did for you," said Judge Thomas today.
When Cummings read about the outcome in the news, his frustration boiled over.
First he took to social media, where he made threats to kill people involved with the case, as well as adverse comments regarding the Dunedin City Council.
"You will all be getting it to between your eyes today out and about with my shooters today look out if you're done me wrong," [sic] he wrote.
Police visited Cummings' Mosgiel home but he was on his way to central Dunedin.
He entered a law firm's offices with a 30cm wooden baton, court documents said, and asked his lawyer about his legal rights.
Due to the defendant's agitated state, he was asked to leave.
He kicked a hole in a door then broke two computer screens in the reception area before heading to the city council's headquarters.
Still wielding the weapon, Cummings smashed a window then took to a plastic display stand, which he threw against an internal door.
As he tried to smash another glass door with a chair, staff activated a panic alarm and police soon swarmed the area, apprehending him in Moray Place near the library.
When he was later interviewed, Cummings said he was "struggling" with his daughter's death and had "reacted" when he read the news story.
Counsel James Olsen argued the defendant should simply be convicted and discharged given the psychological work he had done and the fact he spent five months in prison on remand.
"The court should draw a line in the sand ... he's not going to go out and offend, he's over this," Olsen said.
Judge Evangelos Thomas said the defendant had "endured every parent's worst nightmare".
"I imagine nobody understands quite what it involves until they're desperately unfortunate enough to find themselves in that position."
Cummings had "well and truly" done his punishment and all that was left was giving structured oversight for his future, he said.
Judge Thomas imposed nine months' intensive supervision and ordered Cummings to pay $1985 for the damage caused at the law firm.
