The mother and grandmother of a preschooler who set the New Plymouth Pak'N Save on fire causing $720,000 of damage were fined $500 each yesterday.
At the New Plymouth District Court the women both pleaded guilty to the charge of leaving a child under 14 without adequate supervision.
On July 11, the supermarket was evacuated after it was filled with toxic smoke from a fire in the nappy aisle.
The supermarket remained closed for a day while hundreds of thousands of dollars of ruined stock was thrown out and replaced.
Because of the age of the child, who is too young to be charged, community magistrate Lesley Jensen ordered name suppression for the child and the women.
She said paying reparation to the supermarket was "far beyond the means of the families", and took into account the families were receiving help from Child, Youth and Family and the children were undertaking a fire safety course with the Fire Service.
"This is probably a wake-up call for all of us who have young children to keep a better eye on them," she said.
The pair had two other young children with them at the time.
She also said most of Pak'N Save's costs would be covered by insurance, although they had an excess of $5000. The police summary of facts said the women admitted the child ran away from them as soon as they walked through the supermarket doors.
It was not unusual for the boy to tear off and return with an item he would ask his mother to buy, they said.
He was unsupervised for 12 minutes before store staff helped his grandmother locate him.
At 3.51pm CCTV footage showed the boy going into aisle six and reaching down into the lowest shelf ,which held nappies.
Two minutes later he skipped down the aisle and smoke could be seen coming from where he had been.
He then went back and kicked nappies off the shelf, which the summary said could be seen as an attempt to encourage or check on the fire.
By 3.56pm flames had reached the top of the shelving units and Pak'N Save staff turned up and managed to control the fire until the fire brigade arrived.
The summary said the boy's mother had later realised he had started the fire, and thought he had used a lighter, but it was found he used matches from the supermarket.
She said she was nervous and worried and not sure how to go about reporting it to police.
The women were identified by police after photos of them were run in the Taranaki Daily News.
The magistrate said Pak'N Save could attempt to recover money from the women through a civil court case.
- Taranaki Daily News