This document aims to identify best practices for criminal and medicolegal investigation in child and teen homicide cases. For this purpose, information was collected related to regulations, institutional characteristics, and procedures for the criminal investigation of these cases in Spain, the United Kingdom (UK), France, and the United States (USA). Significant differences were observed between Chile and the countries studied, primarily when compared to the USA and the UK. The existence of coroners, the clearly defined roles of prosecution and investigation between public prosecutors and police officers, the establishment of standards guiding detection of these homicides, and the role of private forensic entities are the most substantial differences when compared to the reality in Chile.