According to Gregg Lee Carter , an American sociologist who studies gun violence in the United States , the firearm was designed to comply with the 1994 Federal Assault Weapons Ban . The Bushmaster XM15-E2S " M4 type " carbine gained notoriety for its use in the October 2002 Beltway sniper attacks . A Bushmaster XM-15 was used in the December 2012 Sandy Hook Elementary School shooting . Nine families ( plaintiffs ) of the 26 victims of the shooting filed a class action lawsuit in Connecticut against Bushmaster , Remington Arms and others ( defendants ) seeking " unspecified " damages , claiming an exemption in the 2005 Protection of Lawful Commerce in Arms Act which would normally disallow such a suit . The plaintiffs alleged that the XM15-E2S was only suitable for military and policing applications , and Bushmaster had inappropriately marketed the firearm to civilians . The case was dismissed in superior court and is being appealed to the Connecticut Supreme Court . An XM-15 was also used in the 2018 Nashville Waffle House shooting
Sandy Hook Elementary School shooting
Sandy Hook Elementary School shooting
Bushmaster XM-15