Social Development Minister Paula Bennett wants to know whether Child, Youth and Family properly assessed a Lower Hutt family where the children were neglected and in need of medical care.
The parents have pleaded guilty to four charges of not providing the children with their most basic needs.
Police removed the four children from their parents during a party at their house.
Child, Youth and Family put the children with a family member, but police found them back with their parents days later.
Ms Bennett said she is looking into whether Child, Youth and Family followed the correct assessment procedures.