Countries such as Canada, UK, France and Germany have all enforced the game rating system with laws and since doing so have had a reduction in crime rates, but the US hasn't./quote]
The first rule you are taught in any research methods course is "correlation does not imply causation".
And where did you hear that crime is not reduced in the United States?
This article features statistics from the department of Justice and the FBI and shows a downward trend in violent crime. In fact, violent crime rose sharply in the late 70s and 80s, when Pong and Pac-Man were the video game fare. I guess this means that the Atari 2600 was responsible for gang violence...