Reports that the gunman in the Sandy Hook Elementary School shooting in Newtown spent much of his time playing violent video games has sparked three legislative proposals to study the behavioral effect of the games and whether to limit their availability to young people.

A public hearing of the legislature's Children Committee is scheduled Tuesday on a bill that would prohibit minors from playing certain violent games in arcades and create a task force to study the effects of violent games on behavior.

That bill, introduced by Sen. Toni Harp, D-New Haven, was originally proposed in an earlier form shortly after the 1999 Columbine shootings. It passed both the Senate and House, but Gov. John Rowland vetoed it.

Another bill, introduced by State Rep. DebraLee Hovey, a Republican who represents Newtown and Monroe, would place an additional tax on violent video games, the proceeds of which would go toward funding studies and educating parents about the games.

"I've talked to parents and they have no idea of the anti-social themes and the level of violence that are in these games," Hovey said. "Children who are developing their brains and their personalities really do not need to be playing these games. They have a negative impact on their ability to develop compassion and empathy."

There are hundreds of studies on how video games affect those who play them, but also a fair amount of disagreement over how conclusive those studies are.

"Every study can be argued in two different directions," said David Greenfield, a professor of psychiatry at the University of Connecticut and founder of the Center for Internet and Technology Addiction. He argues in the direction that violent video games do pose a danger to young people.

"It conveys two things — a lack of respect for human life and a desensitization to violent acts," he said. "And it teaches them the skill set to enact the violent act with increased precision. And we call that entertainment."

Brad Bushman, a psychologist at Ohio State University, co-authored a meta-study that examined 380 studies on video games.

"The results show that violent video games increase angry thoughts, aggressive behavior, and they decrease helping behavior and decrease empathy and compassion for others," Bushman said.

Bushman said he often hears an argument from video game players: "I play violent video games and I've never killed anyone."

"Is that the measure?" he said, adding that aggression usually plays out in more subtle ways. "I want to know how you treat your friends, other drivers on the road and your parents."

Chris Ferguson, who teaches psychology at Texas A&M, disputes that the body of research is as consistent as Bushman claims. He compares the fears about video games to those expressed about comic books in the 1950s.

The field of video game study, Ferguson said, is plagued by confirmation bias, in which researchers ignore evidence that doesn't fit with preconceived notions. For instance, he said, there was no discussion about video games when Amy Bishop, a biologist at the University of Alabama in Huntsville, shot and killed three people and wounded three others at a faculty meeting. That's because Bishop doesn't fit the stereotype of a violent game player, he said.

"With Adam Lanza, it would be weird if he didn't play violent video games, because 80 to 90 percent of people in that age group play violent video games," he said.

Ferguson said the ways that are commonly used to measure aggression in a lab setting – including how willing participants are to blast noises in the headphones of fellow subjects or put hot pepper in other participants' food - don't correlate to real life violence and aggression. They also measure only temporary effects, he said.

Even researchers convinced of a link between aggression and violent video games say the question is particularly murky when considering extreme acts of violence like the Newtown shootings. Craig Anderson, who teaches psychology at Iowa State University, said there are no easy answers about that kind of violence.

"When we get these extremely awful incidents, you get so-called experts saying this caused it or that caused it, but any 'expert' who says this, they're wrong — there's no one cause," he said. "Those kinds of extreme behaviors occur not when there's one or two or even three risk factors, but when there are multiple risk factors."

But Anderson said playing violent games could be one those risk factors.

"What we find is that those who play a lot more video games behave more aggressively even after you control for a number of different variables," he said. Anderson said video game players are more likely to see the actions of others as being hostile. If a child gets bumped by another student, for instance, that child is more likely to see it as an intentional act than as an accident.