How more gun tracing can help Canada clamp down on cross-border trafficking

Amid a rise in shootings in major Canadian cities, some experts who study firearms trafficking say the country needs to drastically increase the number of firearms traced through the U.S. Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF). In part 3 of Story of a Gun, Tracy Tong looks at how firearm tracing could help lessen the number of gun-related crimes.