Open Baltimore: Crime by month
Mayor Stephanie Rawlings-Blake's Open Baltimore initiative has made a trove of data about city crime available, and one of the first things I wanted to do with my limited technical skills was to use the crime by month data to analyze trends over the course of the year. We've long had access to weekly crime data, but haven't had a clean, month-by-month breakdown until now. One major hangup is that the data does not include December, but we'll work around that.
Since last year, people have been tweaking the city's crime declines as simply a function of the bad weather brought on by the "Snowpocalypse" early in the year. That's largely unfair, as there has been a sustained reduction in crime - particularly violent crime - going back three years now. But the data also confirms those assumptions that there was a dramatic plunge in most types of crimes in February, when the worst of the snow hit. Be it the overall cold weather, the snow, the fact that the month is the shortest of the year, or a combination of all three, February was unquestionably good for the bottom line.
Let's take a look first at property crimes:
As you can see, that's a drastic decline, particularly with larcenies and burglaries, which fell to nearly half of the totals recorded in the preceding month. They quickly snapped back in March, and continuing to climb as the whether got warmer, peaking in August. I'm struck less by the low totals in January and February than the relative consistency throughout the rest of the year. Keep in mind too that property crime might not necessarily have dropped to the extent we see here, but that police had limited ability to respond to such lower-priority calls for a stretch during the month.
What about violent crime? Homicides and shootings followed an expected pattern of rising and falling in the spring and fall. Robberies, however, followed a curious pattern.
Whether its an anomaly or some combination of street enforcement and other factors, robberies took a bizarre drop in June, even as the city recorded its highest number of aggravated assaults and third highest number of shootings. The June robbery figure was even 17 percent lower than the January total. I'll explore that in a subsequent post.
Lastly, here's a chart with reports of rape for 2010. You can see the huge spike after The Sun's story in June about the Police Department's ongoing "unfounding" of rape reports that prompted a change in policies for patrol officers and detectives: