Gun control advocates and the National Rifle Association differed at a session this week in Washington, D.C., over the direction federal research on gun violence should take, the Associated Press reports. John Frazer, research director of the NRA's legislative arm, told a committee of experts on guns and public health Tuesday that better data is needed on the benefits of gun ownership, such as peoples' use of firearms to defend themselves. He recommended conducting surveys of inmates to determine how they choose victims, and figuring out how many guns are obtained from private transactions. Currently, transactions by licensed gun dealers require background checks of buyers, but those sold privately do not. Dan Gross, the president of the Brady Campaign to Prevent Gun Violence, focused on obtaining more information on how people get guns and the deaths and injuries the weapons cause. “This is not about developing a policy agenda for guns. This is about developing a research agenda,” said Alan Leshner, chief executive officer of the American Association for the Advancement of Science, who heads a committee that will recommend research on gun violence. The committee met at the National Academies of Science.