The map of hidden homicides in Brazil between 1996 and 2021

Those interested in measuring violent crime use the number of homicides, based on the never-verified assumption that the seriousness of the crime implies negligible underreporting. In Brazil, the Mortality Information System (SIM) is the source usually used to measure the number of homicides. Between 1996 and 2021, among deaths from external causes, 8.2% were classified as deaths from external causes of undetermined intent (MVCI), indicating the possibility of homicide underreporting. From the microdata on external cause deaths recorded in the SIM, a supervised learning algorithm learns the characteristics of homicides, accidents and suicides and estimates the probability that MVCIs are homicides incorrectly recorded as MVCI, allowing us to estimate the number of shadow homicides in the SIM. The result suggests that between 1996 and 2021, 128,567 shadow homicides were not accounted for, or 43.6% of MVCI s are actually homicides. Evidence contrary to the hypothesis of reduced underreporting, implying significant impacts on public policy evaluations, econometric procedures and the need to account for these hidden homicides in crime measurements.