A new study published in Springer’s Journal of Youth and Adolescence. found that teens who play violent video games are not likely to become more violent or partake in anti-social behavior.
http://www.springer.com/about+springer/media/springer+select?SGWID=0-11001-6-1433942-0
Reference: Ferguson C.J, Olson C. (2013). Video game violence among ‘vulnerable’ populations: the impact of violent games on delinquency and bullying among children with clinically elevated depression or attention deficit symptoms, Journal of Youth and Adolescence. DOI 10.1007/s10964-013-9986-5