Steve Sailer's been dealing with another potential explanation, lead, for the significant downtrend in violent crime rates that occured in the nineties after having risen steadily throughout the eighties. He blew up Steven Levitt's explanation by, essentially, pointing out that data at the national level clearly contradicted what the abortion-cut-crime theory would predict. There's also the crack epidemic and a burgeoning incarceration rate that meant more thugs removed from society. Identifying any single factor to explain such a complex phenomenon is inevitably going to come up short to some extent.
Still, I wonder how video game sales track with criminality in the US. I've not been able to find historical numbers extending back into the mid-nineties and before. Tracking at the national level is difficult enough--by market is probably impossible prior to the mid-nineties when video games became a cultural staple. If known numbers are floating around out there somewhere, please let me know.
A 'hypothesis' goes something like this: The teen homicide rate shot up the year of the video game 'crash' in 1983. Nintendo resuscitated the market in the late eighties. Sega responded with the Genesis in 1990. Nintendo countered with the Super NES the following year. With 16-bit systems taking video game graphics and play control to a captivating new level (recall how stunning Sonic 2 was for 1992), and a nationally-released movie to premiere what would become one of the best-selling games of all time under the belt, the homicide rate peaked in '91 and began its steady decline (which is now reversing, presumably due to demographics). All of this was now available at home, without requiring a bunch of young punks to meet up at a seedy arcade in town. A new avenue for pent-up male aggression had now become mainstreamed, and as the complexity of this interactive opiate grew, so idle hands no longer were thanks to the control pad.
If nothing else, it'd be interesting to see the strength of the inverse correlation between violent crime rates and video game sales.