Weighing the evidence on video game violence

Scientific evidence suggests violent video games promote real life violence. No wait. Scientific evidence indicates there is no direct relationship between real life violence and violent video games. Who’s right?

“The evidence suggests that those who argue violent video games are harmful have a lot more experience and stronger credentials than those who argue otherwise,” said Brad Bushman, professor of communication and psychology at Ohio State University and co-author of a new study about the scientific evidence regarding violence and video games.

The researchers developed a novel method to consider that question: they analyzed the research output of experts who filed a brief in the U.S. Supreme Court case, Schwarzenegger v. Entertainment Merchants Association (case no. 08-1448). The case asked the Court to decide whether the state of California can ban the sale or rental of violent video games to children under the age of 18. A ruling in the case is expected in the summer of 2011.

NOTE: The California law in question defines “violent video games” as those whose range of options available to the player includes killing, maiming, dismembering and/or sexually assaulting an image of a human being AND the depiction of such act(s) is offensive. 

In the case, groups supporting and opposing the law have filed what are called briefs of amicus curiae. These are briefs by people or groups who are not directly involved in the case but want to offer the court their expert opinion on the issues involved.

The researchers, Bushman, Craig Anderson, professor of psychology at Iowa State University, and Deana Polland Sacks, professor of law Texas Southern University, analyzed the credentials of the 115 people who signed the Gruel brief believing video violence is harmful, and the 82 signers of the Millett brief, who believe video violence is not harmful. (The briefs are named after the lead attorney representing each side.)

“We took what I think is a very objective approach: we looked at the individuals on both sides of the debate and determined if they actually have expertise in the subjects in which they call themselves experts,” Bushman explains.

For each of the signers of the two briefs, the researchers calculated how many articles and books they published on issues relating to violence and aggression in general and on media violence specifically,

The results reveal that 60 percent of the Gruel brief signers (video game violence is harmful) have published at least one scientific study on aggression or violence in general, compared to only 17 percent of Millett brief signers. Moreover, when the researchers look specifically at the subject of media violence, 37 percent of Gruel brief signers have published at least one study in that area, compared to just 13 percent of the Millett brief signers.

In further analysis, Bushman and Anderson examined the academic journals and publishing houses where the signers of both briefs have published their research. They utilized a well-established formula, called the impact factor, to determine the top-tier journals (those with the highest standards and most rigorous peer review) and then calculated how many signers had published in these journals. The results indicated signers of the Gruel brief had published 48 times more studies in top-tier journals than did those who signed the Millett brief.

“That’s a staggering difference,” Bushman said. “It provides strong support for the argument that video game violence is indeed harmful.”

The study was conducted not to validate the position that violent video games pose risks to young people but to demonstrate that there is a way in which the U.S. Supreme Court can impartially weigh the evidence presented in two contradictory briefs.

The problem, however, is that this type of study is not done for every case that is a “battle of experts”. Neither does the study explore where the signers fall within the general scientific community. Yes, one party presented  a stronger argument. That does not mean they presented an accurate argument. Further, there are other issues in the cases besides who has more or better experts. These are important considerations because one of the findings of the lower court was that the studies presented by California in support of their law censoring violent video games was that the studies presented in not support the finding that violent video games actually harmed the psychological health of minors.

“The justices were presented with two briefs, arguing opposite sides, and they may think the contradictory briefs simply cancel each other out,” Bushman said.

“We just wanted to point out to the justices that not all briefs are the same. In this case, the credentials and experience of those who signed the Gruel brief far exceeds that of the ones who signed the Millett brief.”