Wednesday, June 21, 2006

Statistics: The Decline of Rape

From the Post:

The number of rapes per capita in the United States has plunged by more than 85 percent since the 1970s, and reported rape fell last year even while other violent offenses increased, according to federal crime data.

This seemingly stunning reduction in sexual violence has been so consistent over the past two decades that some experts say they have started to believe it is accurate, even if they cannot fully explain why it is occurring.

I'm pretty familiar with the data collection methods used to measure this. The decline is real, and here's why...

Rape is one of the most un-reported crimes. Victims are far more likely to report a theft, and hospitals are required to report injuries that might be the result of an assault. So we have a pretty accurate count on how many cars have been taken and how many people have been shot, but a less accurate count of how many sexual assaults have happened. Women are most likely to be raped by people they know, rape has a huge stigma attached to it, and proving rape has often been difficult.

But things have changed for the better.

DNA identification technology has gotten much better. Proving guilt in a courtroom has become much easier.

Once convicted, they face increasingly harsh sentences. In the 1950's it was not uncommon for rapists to get short prison sentences, and often just probation. No longer - numerous states have seriously considered chemical castration and the death penalty for rapists. At a minimum you will net you at least 25 years in prison, until you're too old to be much of a threat.

In addition, under new laws if a woman is drunk or otherwise impaired and then claims that it was rape, even after the fact, then its rape. This makes an entire category of "fraternity rapes" or other alcohol induced sexual assaults much easier to prosecute and somewhat less frequent, even though its obviously still a big problem.

There is also a hidden demographic side to this story as well. The baby boom is getting much older. So the proportion of our population that is 16-30 and male (the most "crime prone" sub-group) is in steep decline. Older men commit crimes with far less frequency, so all crime has been declining. This is especially true for rape, which clearly has a biological component as part of the problem.

On the numbers side, and this is a little convoluted, so bear with me: Current rape statistics are underreported. But they have ALWAYS BEEN underreported. So even if the true numbers are much higher, the old numbers should have been much higher as well, so the decline is statistically significant and real, even if the raw numbers aren't. Unless for some reason rape has become further underreported in the last 30 years, and there's no evidence of that. If anything, current measurement techniques are much better then 30 years ago.

And finally, though this is by far the hardest thing to prove, I think there has been a cultural change as well. Women are more empowered then they were thirty years ago. There have been massive, somewhat successful "no means no" campaigns. And I think most men have changed as well. Once, it was thought that if a woman was raped, "she was asking for it" somehow. Now virtually everyone rejects that argument, and rape is widely considered one of the most heinous crimes anyone can commit, as it should be.

So, some good news for a change. I had forgotten what it was like.
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