Adam Lanza 's mother bought a semiautomatic Bushmaster rifle at Riverview Gun Sales . Lanza used that gun to kill 20 children and 6 adults at Sandy Hook Elementary School . The ATF conducted more than 11,400 firearms compliance inspections in 2012 . The shooter was able to buy the weapon because he had been denied his right under federal law to purchase firearms from licensed dealers, which is why it took so long for authorities to find him. A detective suspects gun sales at the store were stopped due to poor record keeping .
Adam Lanza 's mother bought a semiautomatic Bushmaster rifle at Riverview Gun Sales . Lanza used that gun to kill 20 children and 6 adults at Sandy Hook Elementary School . The shooter was able to buy the weapon because he had been denied his right under federal law to purchase firearms from licensed dealers, which is why it took so long for authorities to find him. A detective suspects gun sales at the store were stopped due to poor record keeping .