A case of a chest tube placed on the wrong side during a trauma resuscitation in the emergency department is presented as an example of medical injury. Two traditional models, the legal model and the managerial model, are described and their application to medical injury discussed. A new public health model is then applied to the case example as a more effective way to address medical injury. The public health model addresses the injury event rather than the error itself using Haddon's matrix as a framework. Pre-event, event, and post-event phases are examined to find the weakest link, where intervention has the highest likelihood of successfully preventing future injuries.