Thousands tuning in for the verdict saw it - but TVNZ asked YouTube to remove the clip, saying it was a "switching mistake".
A spokesperson said Petrie's fist pump was in celebration of the Christchurch TVNZ news team beating TV3, not the result of the trial.
Ahead of Britain's Prime Minister Boris Johnson's resignation today, the nation's media have followed every development with live coverage as the public has been glued to the tragic political theatre.
Thanks to an error at the BBC, Brits were treated to a look behind the scenes yesterday showing the media were equally stuck to their smartphones as Bojo crumbled.
During a live cross from outside 10 Downing Street, the camera suddenly cut back to Tim Willcox in the studio.
But rather than diligently shuffling his papers or stroking his chin as one might expect, Willcox was instead caught scrolling through his phone with his feet up on the desk.
The moment quickly went viral, with thousands seeing it live and many more watching it online as videos spread across the internet.
Users described the gaffe as "a moment of light relief" and others milked it for a bit of comedy.