-hard to dismantle relationship between body shape and criminality (likely criminality causes body shape) for someone to become a successful criminal, they might change their appearance to be more muscular so they are feared
-relationship between body shape and crime might not be direct (WC males more likely to be convicted of a crime, their jobs would be physically demanding so their acquire the muscular physique so crime is more influenced by social class than body type or it could be a combination of all factors)