The findings of the evaluation suggest that the Supreme Court of Canada attempt to define unreasonable use of force was arbitrary and not grounded in the reality of child physical maltreatment. Most maltreated children are maltreated by their parents, are between the ages of 2 and 12 years, are capable of learning from correction, and are not struck with objects. In addition, three-quarters of child maltreatment incidents take place within a corrective context. One in five cases of substantiated physical maltreatment cases in Canada are not characterized by any of the court’s criteria for defining unreasonable force; however, about half of maltreated children experience spanking as a typical form of discipline in their homes. Together, the findings suggest that ending all physical punishment was more likely to reduce physical maltreatment than placing arbitrary limits on its use. In 2004, the supreme court of Canada set out seven criteria to distinguish reasonable from abusive corrective force with children. The purpose was to protect parents from prosecution for assault while attempting to protect children from abuse by delineating a zone of reasonable force. The purpose of this study was to test the validity of those criteria by mapping them onto a nationally representative dataset of substantial cases of physical abuse. Tables and references