Early childhood educators say they have lost confidence in the Teachers Council and have asked the Minister of Education for all teachers' qualifications to be checked.
This follows the conviction of Tracy Hibberd, who was found to have used forged documents to obtain work in an early childhood centre.
The Teachers Council said it had acted appropriately after being alerted to the case, and systems were being set up to prevent it happening again.
But Early Childhood Council chief executive Peter Reynolds said the case showed the Teachers Council had failed to protect the industry - and children - from those with fake qualifications.
He said the Qualifications Authority found the document Hibberd used had 25 differences from a genuine certificate.