IT HAS been a bloody year in Baltimore, Maryland’s largest city. On November 14th the police department reported the city’s 300th homicide in 2015, a total not seen since 1999. The surge in killings in the majority-black city of roughly 623,000 began after the death on April 19th of Freddie Gray, a 25-year-old black man who was fatally injured while in police custody. Since Mr Gray’s death the city has recorded 244 homicides, a 78% increase over the same period in 2014, representing more than 100 additional deaths (see chart). Criminologists and city officials disagree as to the causes. Some say police have deliberately pulled back from poor, black neighbourhoods, a theory that the police disputes. Others blame an influx of drugs from pharmacies looted during the April riots.

In graphics: America's guns A third theory is that a decline in trust between the police and the policed has had deadly consequences: fewer residents talk to the police, which leads to fewer murders being solved, which—by lowering the odds of being caught—results in more murders. Whatever the reason, the killing continues. Just hours after the 300th murder, police reported a shooting in the city’s Westport neighbourhood, the fourth homicide of the day. The total for the year now stands at 305.