A judge has thrown out charges of sexual and physical abuse arising from allegations made by a group of Porirua children.
The children's parents and another man have been on trial in the High Court in Wellington for the past two weeks.
The children were removed from their parents in 2010 and the authorities were alerted by a caregiver who saw the siblings behaving towards each other in a sexualised way.
In recorded interviews, the siblings spoke of being sexually abused by both their mother and father and the third accused.
They also said they'd been tied up and fed spiders and snails.
Justice Mackenzie told the jury on Thursday he believed the children's evidence on those matters was unreliable and it would be unsafe to enter convictions based on it.
He discharged all three accused on those charges and granted them permanent name suppression.
The parents will be back in court next week on separate charges relating to alleged neglect of their children.