A very interesting point was brought up in the article "Introduction" by Martin Barker and Julian Petley. Sometimes it is not that the counter argument doesn't exist, but rather, it is our choice to not hear or see it. They mentions in the article that, the popular theory became so popular and widely-accepted was because "they were what every politician and newspaper wanted to hear." (p1) This is somewhat similar to the knowledge gap effect, that when an individual becomes interested in a topic, s/he would actively to go out and look to information that is related to this topic. The public audiences usually already have their opinion about the effect of media violence, and they would only pay attention to these report or media coverage that reinforces their original belief.
Barken and Petley is trying to challenge the mainstream tradition of what media violence is, but right away they recognizes that it will be a rocky road. "When we tried to state the opposite case, no one wanted to hear." (p 3) Remember how media is not very efficient in changing what others think, in general it is just extremely difficult in changing other's opinions once they have already set their mind on it, especially when the first impression is so strong. The "specialist" and "researchers" carefully crafts their messages with very establish languages, so that it is almost impossible to response to them. That group people, usually not even media academics, but "a group of psychologists, psychiatrists, and paediatricians" (p 2) who has no expertise in media primes the public's mind about the danger of media violence, and makes no room for others. What summarizes their conclusion is the statement "academic work whose methods and conclusions support populist, 'common-sen' assumptions and gel with newspapers' own ideological positions is far more likely to receive coverage than that which doesn't." (p 8 )