Rates of violence respond to certain features of the environment, such as the incentives of an effective police and criminal justice system and the surrounding norms of legitimate retaliation, but not to video games.

Judged as of 2013-03-12 against the research consensus at that time. The claim has two parts: (a) violence rates respond to environmental features such as effective policing and criminal justice and norms of retaliation; (b) they do not respond to video games. True: research at the time supported (a), and population-level evidence showed no link between video-game use and real-world violence rates. Mostly true: (a) was well supported and (b) was largely supported, but the 'not to video games' part was stated more firmly than the then-contested lab literature on aggression allowed. Mixed: one part was well supported and the other was genuinely contested or unproven. Mostly false: (a) was only weakly supported, or there was substantial evidence that video games raise violence rates. False: evidence at the time contradicted both parts.

Set before the research began.

1. E1 What Can Police Do to Reduce Crime, Disorder, and Fear? The Annals of the American Academy of Political and Social Science (article by David Weisburd and John E. Eck) · May 2004

   “The strongest evidence of police effectiveness in reducing crime and disorder is found in the case of geographically focused police practices, such as hot-spots policing.”

2. E2 What Can Police Do to Reduce Crime, Disorder, and Fear? The Annals of the American Academy of Political and Social Science (article by David Weisburd and John E. Eck) · May 2004

   “These experiments found deterrent effects of arrest in two cities and no effect of arrest in three other cities”

3. E3 TAMIU Professor Publishes Research on Media Influence on Kids, Young Adults Texas A&M International University · 29 January 2009

   “The wealth of evidence, from social science research on video games, to governmental reports and legal cases, to real-world data on crime, fails to establish a link between violent video games and violent crimes, including school shootings.”

4. E4 ISU study proves conclusively that violent video game play makes more aggressive kids - News Service - Iowa State University Iowa State University News Service · March 2010

   “It reports that exposure to violent video games is a causal risk factor for increased aggressive thoughts and behavior, and decreased empathy and prosocial behavior in youths.”

On part (a), a 2004 review found strong evidence that focused police practices such as hot-spots policing reduce crime (E1). Arrest-deterrence results were mixed across cities (E2), and none of the evidence covers norms of retaliation. On part (b), a 2009 university release on a professor's research said the evidence, including real-world crime data, fails to establish a link between violent video games and violent crimes (E3). A 2010 Iowa State University release reported that exposure to violent video games is a causal risk factor for increased aggressive thoughts and behaviour in youths (E4). Given that contested literature on aggression, the statement that violence rates do not respond to video games was put more firmly than the evidence allowed, which fits the criteria's "mostly true" category.