This review of the 91 English children’s services departments with specific policies on bruising in pre-mobile children found a major disjuncture between research evidence and its interpretation in guidance. Many policies require all pre-mobile children found with a bruise to be seen urgently by a paediatrician and in some all bruised children are subject of a formal child protection investigation regardless of the explanations for the bruise or the views of front-line practitioners. However, the research on bruises in pre-mobile children on which these policies were based was found to be limited and contradictory and did not fully support the guidance given. National guidance given by the National Institute for Care and Health Excellence and many policies state that bruising in pre-mobile children is suggestive of physical abuse because accidental bruising is uncommon despite the only longitudinal study of bruising showing 27% of pre-mobile children were bruised over an average of 7.6 weekly observations. The paper calls for an urgent review of these policies and guidance and improved standards for policy making.