The mass shooting in Virginia Beach that left 12 people dead has reignited the debate about silencers. The gunman used at least one .45-caliber pistol with a suppressor. CBS News' Errol Barnett has the latest on the investigation, and then retired ATF agent David Chipman, a senior policy advisor at Giffords, joins CBSN to discuss whether the devices can make a mass shooting more lethal.
