In 2015 homicide rates in Boston reached a 15-year low, with a total of 40 killings, according to the Boston Globe. Last year, while the number of non-fatal shootings dropped, homicide rates in the state capital increased by 15 percent, to 46 murders. This uptick in killings coincides with an increase in numbers for some large cities across the country.

Boston Police Department Homicide Unit records, published on the unit’s webpage, include entries for both solved and unsolved murders. These lists include the names of victims, the month each homicide occurred, and the shooting location. Patterns and increases across 2015 and 2016, along with recurring locations, provide insight into causes of and preventative action for homicides in Boston.

Homicides per month 

In 2016, the number of homicides in the city rose significantly in the months of June and October. From June 2015 to June 2016, killings for that month increased by 5 deaths. The increase is more startling for the month of October  – in 2016 there were 8 deaths, up from 0 in 2015.

Source: BPD Homicide Unit

Homicide data from the Boston Police contained some unexplained discrepancies. The data reports 38 homicides for 2015 and 43 in 2016. This leaves out two deaths in 2015 and three deaths in 2016, as reported by the Boston Globe. Because of this, data in the graph above may not account for all murders over the two-year period. Based on Homicide Unit data, killings in Boston increased by 13 percent between 2015 and 2016.

Homicide hot spots 

The map below represents the locations – and corresponding frequencies of both solved and unsolved homicides – provided by the Homicide Unit for 2015 and 2016. The areas in purple are the locations with the highest frequency of homicide; the areas in blue indicate locations with a lower frequency of homicide, with most locations totaling one homicide over the two-year period.

Clearance rates 

While 2016 marked an increase in homicides for the city of Boston, it also marked in increase in completed homicide investigations for the Boston Police Department. According to the Boston Globe, a spokesperson for the department reported a 63 percent clearance rate for 2016, up by two percent from the rate in 2015.

The increase in closed cases followed a five-year period, from 2007 to 2011, when homicide detectives had cleared only 148 of 314 killings, with a clearance rate of 47 percent. Rates began to increase in 2012, when the department received funding from a grant from the US Bureau of Justice Assistance Smart Policing Initiative. Over the next three years, detectives cleared 86 of 151 killings, with a clearance rate of 57 percent.

Source: Boston Globe

Methods

The data used in this analysis was retrieved from the Boston Police Department Homicide Unit webpage. Sorting began by indicating the names of homicide victims,  shooting locations, the month in which each homicide occurred, and whether the case was solved or unsolved. To find the increase in homicide counts per month, and the overall increase from 2015 to 2016, this information was rearranged using Excel pivot tables. The latitude and longitude coordinates of the shooting locations set the parameters and gradient for the heat map.