All counts refer to police reports (averiguaciones previas which may contain more than one victim) since that is the only information available at the municipio level. All rates are annualized and calculated using 30 day months.
The charts include the 50 most violent municipios with more than 50,000 persons during the last 12 months. The charts are ordered from highest to lowest homicide rate during the last month with available data.
INEGI homicide data tends to be more precise. Forensic coroners and the INEGI simply don't have the same incentives to lower the number of homicides that happen in Mexico as the police. In addition to adding deaths from Legal intervention, operations of war, military operations, and terrorism to the INEGI homicide count I used a statistical model to predict the intent of deaths of unknown intent similar to what I used in this post. The disadvantage of using the INEGI data is it is usally more than a year out of date.
Intuitively, you can think of the statistical model as if someone were to ask you to guess the injury intent in the death of a 70 year old Mérida woman whose cause of death was transport related. You would probably answer it was an accident. On the other hand, if you had to guess the type of death of a young adult male whose cause of death was a firearm, and the injury took place on a public street in Ciudad Juárez, you would probably guess it was a homicide.