Trulia has produced another wonderful interactive chart, this time showing various types of crime, and what time of day they occur in 25 of America's largest cities.
Trulia has taken a stab (pun intended) at this data before, in a map showing exactly where crimes occur in a given city. But by offering this data as a time series, it actually ends up being even more interesting, from a sociological point of view. The fact is, the various categories of crime imply different states of mind in the criminal, and as a result, they have a different ebb and flow throughout the day.
Take assaults, for instance. The impulse to beat on someone is clearly crime of passion -- it's not a crime of opportunity. You punch someone because you're angry, and people get angry all throughout the day. Given that, check out this chart. The timeline is organized from 12:00am to 11:59pm:
As you can see, once you throw out the hours of 3-5 a.m., when most people are asleep, assaults actually happen at a pretty even pace throughout the day. Mornings, afternoons and nights: They're all equally good times for getting pulled into some argument where a fist flies.
Contrast that with robberies. These are clearly crimes of opportunity: You rob someone with a fair bit of premeditation, and your chief concern is not getting caught. Ergo, robberies usually happen during the day, with peak reporting at about 5 p.m. Why then? Probably because that's when people start arriving home from work to discover they've been robbed:
Of course, the one exception seems to be Philadelphia, where people get robbed all the time, no matter if the streets are busy, people are home, or whatever. That seems baffling until you think about it a little. There probably comes a point when a city is so high crime that criminals aren't too afraid of ever getting caught. Hence, they can get away with all kinds of stuff no matter who sees them -- there's a tipping point where crime goes from being a transitory, temporal thing to a culture that's self-sustaining and hard to check. Philadelphia, for anyone who's ever spent any time there, would seem to confirm this: The hoodlum culture there is nearly unchecked, and you can hear plenty of stories of people getting robbed or shot in broad daylight.
Which brings us to shootings. These are clearly the most heavy-duty crime, and the one where the consequences of getting caught are the most dire. As a result, they tend to happen in the wee hours when there's less likely to be witnesses:
Which isn't to say that shootings are always planned. But you have to believe that the chances of getting seen and caught weigh in the back of the mind of anyone thinking about pulling out a gun.
Check out the entire fascinating series of charts here.