A fatal nail gun injury--an unusual ricochet?

An 18-year-old construction worker suddenly collapsed while handling a power-actuated nail gun and died shortly after. A neat, almost circular puncture wound was found on the front of his left chest. No fire-arm residues were detected on the surrounding skin. The police stated that it was an accidental injury, at a construction site, where a nail fired from a nail gun by the deceased had deflected off the wall and struck him on the front of the chest. Since the entry wound appeared to be a neat hole, and that too on the front of the left chest overlying the heart area, there was reluctance on the part of the pathologist to accept it as an accidental injury due to a ricochet. A visit to the scene, interrogation of witnesses, examination of the alleged tool and post-mortem X-ray of the deceased were undertaken prior to autopsy. A bent nail was found in the heart. The scene visit and the subsequent autopsy revealed that the nail took a roughly circular flightpath after it had struck the wall, all the while travelling with its pointed end directed forward. Within the body too, the nail maintained the same path. Various medicolegal issues are discussed pertaining to nail-gun injuries. The importance of a visit to the scene, examination of the alleged tool, interrogation of witnesses and the X-ray of the body, all prior to autopsy, are emphasized. The conclusion was: accidental death due to the unusual ricochet of a nail.