Peter TurchinPeter Turchin is a professor of ecology and mathematics at the University of Connecticut and author of War and Peace and War: The Life Cycles of Imperial Nations. Much of his work concerns a new field known as cliodynamics, which attempts to discover general principles that explain the functioning and dynamics of historical societies. He has agreed to be a guest blogger this week; this is his first of two posts.
Why Are Killing Rampages Increasing?
By Peter Turchin
A Guest Post
So far in 2008, The New York Times reported at least six shooting rampages. Just two weeks ago a man shot or stabbed 10 people in northwest Washington, six of whom died. After his arrest, he told the police that God told him what to do and told him to “kill evil.”
Are these episodes of senseless mass murder increasing? A systematic search of The New York Times from 1946 to the present suggests that the increase is real and very dramatic:
Number per year, plotted by decade.Over the last half-century the incidence of massacres — shooting rampages, killing sprees, etc. — increased roughly 10-fold. These numbers exclude crime-related (along the lines of Reservoir Dogs) and family-related (“Man Shoots Wife, Kids, Self”) multiple murders.
Why is this happening? Note that I am not concerned here with why killing rampages occur, but why they are on an increase.
The rise in massacres began during the 1960′s and shows no signs of abating. It’s a long-term trend, and I think it is telling us something about fundamental ways in which our society is changing.
I am interested in this trend because my research, in general, focuses on investigating long-term dynamics of historical societies (I call this cliodynamics, Clio being the muse of history). One empirical result from this program is that societies tend to experience recurrent waves of violence and political instability; these waves are themselves the results of long-term social and economic trends (more on this in my book War and Peace and War). In other words, when we want to explain trends evolving on a slow time scale, we look to mechanisms operating on the same scale.
A study by The New York Times in 2000 found that the majority of massacres happen in two situations: at the workplace (about one-third of the total) and at school (one-fifth). Here’s my hypothesis for the increase of work-related rampages (I will deal with school rampages in my next blog):
We know that during the 1970′s something changed in the American economy, and in a very fundamental way. Between 1930 and late 1970′s, real wages grew essentially monotonically (overall, they grew by a factor of 3.5). Since then the wage stagnated (white-collar workers) or even declined (blue-collar workers). These are official statistics (Bureau of Labor Statistics); the actual situation must be worse, because the real rate of inflation is probably underestimated by creative folk at government statistical agencies.
In any case, the costs of big items that define the middle-class way of life — houses, college education, medical insurance — have increased faster than the official inflation rate.
The implications are obvious, and it is surprising that they are rarely brought up in the context of massacres. As their economic prospects deteriorate, many breadwinners find themselves under unendurable pressure to maintain the socially expected level of consumption. Under these conditions, people — whose psychological problems would be borderline in the gentler economic climate of the 1950′s — today “go postal.” So the harsher the economic conditions, the greater the numbers of those whose latent psychological problems develop into full-blown psychosis.
The New York Times from 2000 provides some indirect support for this hypothesis: 57 percent of rampage killers in their database were unemployed when they went on rampage. Remember the 1993 movie Falling Down? The resemblance between the fictional character, brilliantly played by Michael Douglas, and real rampage killers, described in the press reports that I read, is uncanny.
To close, I submit that there is a plausible connection between worsening economic conditions (for most Americans, except the rich) and an increase in workplace rampages. Substantial and growing proportions of massacres, however, occur at schools and universities. I will address this issue in my next blog.
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Now adjust for increases in population size and for changes in how we house (or fail to house) and treat the mentally ill, and changes in population densities (as more of us live in more urban crowded conditions).
My gut feel is that these events have become more frequent, too. But I am cautious about believing it to be true.
It may well be that social stresses tend to bring these kind of mental illness episodes to the surface … and certainly the modernization of our economy and technology is leaving behind an ever growing segment of society that is unable to keep pace or retool/retrain themselves.
There was a time in our nation that mindless brute strength was enough to keep someone employed in a simple agrarian society, and probably making enough to even raise a family. Not too many careers in manure-spreading, chopping down lumber with an axe, making hay by hand, laying track for railroads, mining coal with a pickaxe, or cleaning stalls any more. Even those tasks have become mechanized, and require skills beyond a lot of folks.
So those folks that are incapable of advancing with the rest of our workforce … what happens to them? Poverty, crime, mental disease, drugs, … and we no longer institutionalize those people in a non-criminal setting.
The social stresses have changed a great deal. Failure has a higher price. Perhaps that is why we see these rampages at loci of success/advancement, such as a university or workplace.
Nor can we discount the impact of publicizing these events. The mentally ill or distraught may be more receptive to copy-cat behaviors.
I see a fourteen-fold increase in shooting rampages from about 0.5 in 1947 to about 7 in 2006. What has happened to the overall population since 1940, about the time the graph starts? You’re showing number per year, not number per capita per year. Result is we’re deprived of a valuable measurement and really can’t draw any conclusions from the data as presented. The population roughly tripled over the time your graph presents making the graph, while still concerning, a bit less dire.
Put another way, an increase in data from 0.5 points per year to about four points per year (corrected to per-capita numbers) looks a whole lot less troubling than reporting the “straight” numbers.
My guesses:
a) Population increase. Not only the raw counts, but also more diversity, which always brings along some ethnic conflicts.
b) The increases really started taking off in the 1960′s which parallels the timeline of the rise in civil rights conflicts.
c) Availability of guns. It’s the easiest way to kill a lot of people in a short time.
d) The media, especially TV. Creates copycats, and shows that if you commit these crimes you are guaranteed lots of exposure. Go out blazing.
Um . . . wow?
Also, Professor Turchin, you must be a lot of fun at parties, huh?
. . . wow . . .
First I’d be willing to bet a paycheck that the yearly results going back that far aren’t apples to today’s apples. Meaning I’d bet the % of the total that went unreported by the NY times has decreased over time causing part of your trend increase.
Second, I believe I read, from Caldini (sp?), that there is a copy cat sort of impact. Could part of the rise be from the increase in information communicated over time?
What impact does simple population growth have? Has the density of people increased at all at the point of attack(more targets per square inch)?
This graph looks like it could be correlated with sales of hip hop music as well.
Maybe this has already been cared for – it is a blog post after all. But as it stands this “link” is dubious at best. I think it should come with a warning label.
I assume that your numbers are corrected for population increase during that time?
So there were more rampages in the period from 1930-WWII? And more rampages in the South after the Civil War? And more after the economic panics in the late 19th Century? Or is this ex post facto explanation that doesn’t account for earlier, similar circumstances?
Are rampages being reported more often? For example, it looks like we have a lot of serial killers today, but anyone who has read The Devil in the White City knows they (specifically H.H. Holmes) existed over 100 years ago – and we can’t know the frequency because the era was so different.
Great historical work about the French Medieval period revealed massive amounts of personal crime, with rape being so frequent we might accurately say it was “common.”
Not having access to your data sources, why not say that rampages occur at work and school because we no longer have the same outlets for violent rampages as in the past? That is, you can’t just murder some drunks in San Francisco and walk away like you could in the days when that did happen – and then people were supposedly kidnapped and sold onto ships. Maybe you kill at your workplace because you go there a lot these days rather than walk through the streets of a red light district where people disappear frequently and no one cares? And maybe rampages are reported more often.
“a new field known as cliodynamics, which attempts to discover general principles that explain the functioning and dynamics of historical societies”
Don’t we call that field “history?”