After a rough 2012 defending their actions as homicides soared past 500 killings, Chicago Mayor Rahm Emanuel and police Superintendent Garry McCarthy had what they billed as good news to share yesterday: violence in the first quarter of 2013 fell sharply from a year earlier, reports the Chicago Tribune. The two found themselves on the defensive after disturbances downtown over the weekend by large groups of teens captured national attention and reignited concerns about mayhem along or near the city’s tony Magnificent Mile with warmer weather on the horizon. The Tribune says the “latest contrast shows once again how difficult it can be for Emanuel and his team to get ahead of Chicago’s seemingly pervasive violence — an issue of incredible complexities that despite short-term success can quickly be eclipsed by a high-profile murder of a teenage girl or a scary robbery on a popular [ ] train line.” Last month, homicides fell to 16, the lowest total since 1959, from 52 a year earlier. For 2013’s first three months, homicides totaled 70, a 42 percent drop from 120 for the same period of 2012. Criminologist James Alan Fox of Northeastern University said police walk a tough line when it comes to crime statistics. “When crime numbers go up, invariably the police take too much blame. And it’s really unfair when they’re criticized,” he said. “And then when it goes down, they tend to take a little too much credit too.”