The authors discuss the difference between "correlation" and "causation". For example, I left my job in March 2000 (NOC)when our company stock had been on the decline for a couple of years. That same month, the stock started climbing. In August, 2002 I returned as a full time employee and the stock started dropping. Is there a correlation? YES. Did I cause the stock change? Not in my wildest, narcissistic fantasy.
Steven Levitt offers evidence that the fall of the crime rate in the United States in the 1990's was due to the legalization of abortion two decades earlier. This is a shocking concept to many. There are many people that attempt to refute this theory. I actually believe there is a causal relationship.
The book handles the controversy well by attempting to take a neutral stance. An interesting point the authors make is that the "Pro-Choice" advocates assign a value of zero to an unborn fetus and the "Pro-Life" advocates assign a value of one to an unborn fetus. The authors show that the murder rate has actually increased if you consider the fetus as being only 1/100th of a person.
I would like to offer a different perspective without arguing the validity of the theory. My first reaction to the theory that Abortion reduces crime was strong rejection. But the reasoning makes sense. I would agree that unwanted pregnancies would likely lead to poor parental support and potentially criminal behavior. It doesn't take much however to demonstrate that abortion is a highly unethical approach to fighting crime.
I remember a conversation I had with a Brazilian about the approach used by their neighbor, Paraguay, at fighting crime. He said with admiration, "In Paraguay, if someone commits a crime, they disappear and they never commit a crime again." Sounds good unless you or a loved one are innocent yet falsely accused.
So let's imagine the situation where we don't allow abortions but would like to preserve the advantage of reducing crime. So we allow birth of all fetuses (even if they are only equal to 1/100th of a person ;-). We then institute a much more ethical version of the Paraguan crime solution:
If anyone is convicted of a crime, we kill them.
This is much more ethical than abortion, since any potentially valuable fetuses (Like Barrack Obama or Oprah) are allowed to become productive members of society, yet those that have proven criminal tendencies are terminated. (I hope you find this solution as shockingly unacceptable as I do.)
I believe that the crime epidemic was due to various factors. As with any epidemic, I believe the eventual decrease in crime was inevitable. Natural consequences along with pressures from society reduced crime. There were also other factors like legalized abortion.
Another epidemic that started decades ago was unwanted pregnancies. Is this a value added epidemic that should be sustained by society and nature? I would argue that it is a negative value epidemic. Does abortion sustain or defeat this epidemic? Statistics show that it sustains it.
The fight then shouldn't be about abortion, it should be about how to decrease the complex issue of the unwanted pregnancy epidemic.