A chapter from the book Freakonomics by Steven D. Levitt and Stephen J. Dubner looks at the decrease in crime rates from the 90s on. The authors look at all of the explanations that experts had given on the crime drop which range from innovative policing strategies to aging of the population. After explaining why each of these explanations has little to no effect on the crime drop they go on to offer up a new theory, the reasoning that legalizing abortion causes a decrease in crime rates. They explain that because abortions are more common in poverty stricken and challenged homes the children that would be born are more likely to grow up as criminals.
What i think this chapter is missing is a look at the other side of things and what could disprove their theory. Besides the fact that this theory is opening up a whole new aspect of "what if's" with the abortions but it also completely avoids the other changes that could have caused this decrease as well. Such as the better education children are getting now compared to the past, also the rise of support, after school programs and other efforts that have been put in place concerning children raised in poverty stricken environments. Overall i think it's an interesting theory that doesn't take everything into account and lacks solid evidence.