The evidence has been there in dribs and drabs for years, but a recently published study puts the hole issue to bed in a commanding way:
This article presents 2 studies of the association of media violence rates with societal violence rates. In the first study, movie violence and homicide rates are examined across the 20th century and into the 21st (1920–2005). Throughout the mid-20th century small-to-moderate correlational relationships can be observed between movie violence and homicide rates in the United States. This trend reversed in the early and latter 20th century, with movie violence rates inversely related to homicide rates. In the second study, videogame violence consumption is examined against youth violence rates in the previous 2 decades. Videogame consumption is associated with a decline in youth violence rates. Results suggest that societal consumption of media violence is not predictive of increased societal violence rates.
So there you have it. Those who have worked in the field aren’t likely to be surprised, but the general public will have their preconceptions pretty heavily challenged by this. What’s your take?