Update: See below for crazy theory.
Here are the number of murders and non-negligent manslaughters in cities with at least half a million citizens, from 1985 to 2009, the last year statistics are available. These are from the FBI’s Uniform Crime Reporting Statistics – UCR Data Online tool.
None of these adjust by population, which can lead to wild misinterpretations. For example, look at Detroit, which shows a rapid decline, but which is readily explained by the city’s depopulation. The pictures are most useful in cities whose populations are roughly stable.
The FBI did not include the murders “as a result of the events of September 11, 2001”, but did include those of the Oklahoma City bombing. There are also many “changes in reporting practices, annexations, and/or incomplete data” in the cities. For a complete list of caveats, see the UCR tool.
There is some concern that the murder rate is inching upwards. Yesterday in New York City, for example, there were two shootings, one in a crowd at Brighton Beach (one was killed, one dying, several injured), and at the A train-AirTran interchange in Queens (nobody dead). NYC’s murders in 2010 were 536. There have been 185 bodies added to the stack this year, the same number as there were last year at the same date. The rate thus appears constant.
But the nature of crime appears to be changing. In Chicago most prominently, but also in Washington DC, Boston, NYC, and other large cities large groups of “youths” have gathered together in “marauding” or “flash” mobs whose purpose is to attack, rob, intimidate, and beat. So far, these “youths” have not been blooded, however.
Most cities saw their murders drop. Phoenix was an exception until recently. Tuscon is still an exception. You are not supposed to speculate why: doing so risks a boycott by San Francisco. Indianapolis is a strange exception: people generally blame “teens.”
Update. Crazy Explanatory Theory
Rudy Giuliani was widely credited for bringing down New York City’s notorious murder numbers. But at the same time Giuliani was working his miracle, murders were dropping nearly everywhere else, too. Why?
My guess is the internet and associated computer and entertainment technology.
Just look at when the drops began: the mid to late 1980s. This is when Usenet and Bitnet began, when people began playing with dial-up, independent bulletin boards, a.k.a. BBSs (remember those?). This is also when in-home video games became popular and cheap; when DVDs were introduced.
In other words, this is when people started staying inside routinely, with the consequence that they stayed away from other people. And everybody knows “other people” is the prime motivation for most murders.
The internet began in earnest in the late 1990s, becoming saturated about five to ten years ago.
Now, during this time, cell phones became ubiquitous, but until the past two or three years, these devices were not adequate replacements for computer-based internet surfing, game playing, or video watching. They, and highly portable pad computers, have now become superior, all-in-one devices than stay-at-home, big-box computers.
These “smart” phones can be taken amongst other people, where they will engender envy, a lovely and time-tested motive for murder.
So, if this absurdly speculative theory is correct, once “smart” phones and pad computers reach saturation (say, in ten years), then the murder rates will have increased significantly.
Note that the economy did improve starting in the late 1980s. This is also when the cold war ended, giving us a boost in many ways. But the economy has stank for several years now, as it did after 1998, and we are now at war in three countries, yet the murder rate has not risen (though it may no longer be falling).
Of course, the trends could be purely demographic. The so-called millennium baby boom began in the mid to late 1980s, too. And if you’re at home tending to your kids, you’re not out killing somebody. People are once more having fewer kids (fewer marriages, too), so again, they will head back outside.
(If I were still interested in pumping out papers, I could publish this and secure tenure in a department of sociology!)