When there is an incidence of crime or suspected crime in the form of scuffle, body harm, accident, homicide, resulting into simple, grievous, dangerous injury, or death of human being it become a subject matter of criminal investigation and is treated as medico legal case or in very common word a police case. The legal investigation begins with when, where, how this happened and who are the accused and the priority of the investigator any responsible citizen who are at the scene of incident is to transfer the injured to the nearest suitable hospital. In accordance with Section 39 of Criminal Procedure Code of India it is legal duty of the treating doctor to inform the nearest police station as soon as he/ she completes his primary care. The idea is the earliest legal proceeding so that the maximum evidences could be collected by the police officer as well as minimum destruction of evidences, site of occurrence, could be possible knowingly or unknowingly by any party. The duty of the attending doctor is to record all the injuries, its dimension as far as possible, and the body parts where the injuries are located the nature of injury whether simple or grievous, caused by sharp/blunt object, age or duration of injury and with other vital parameters of the patient, so that specific answers may be given for legal investigation and to book a case under law of land. 

Keywords: Grievous Hurt; Dangerous Weapon; Endangering life; Forensic Expert; Medicolegal opinion.