It is very long though so I'm not sure it's exactly the type of book being requested here. Not that the data is unimportant, but the inclusion of so many tables and tables and charts caused me to give up on trying to finish the book.
* the Flynn Effect
* various points of human psychology (victim vs perpetrator bias)
* the crime spike in the 90's and its causes
* a critique of Freakonomics' hypothesis that abortion caused the decline of the 90's crime wave
* Sections on bullying, animal rights, gay rights, women's rights, etc.
* The various types of wars and their individual proximate causes for decline.
* An interesting section on self-control, how it works and how its lack contributes to crime. Even fascinating pragmatic information on how one's own self-control can be improved.