The Boston Police Department’s Homicide Investigation Unit investigates all homicides occurring within Boston Police jurisdiction. According to FBI standards, the annual homicide clearance rate is calculated using the total number of new homicides in a calendar year, and the total number of homicides that are cleared that calendar year – regardless of the year the homicide occurred within. The reason for this is that homicide investigations can span multiple calendar years. In addition, incidents that happened in previous years can be ruled a homicide years later and added to the current year’s total.