Scores of the guns in Chicago are trafficked from outside the state. From a story by Jason Meisner in the Tribune:
On a Sunday afternoon last May, a man identifying himself as Chris Hendridge pulled up to a grocery store parking lot in Louisville, Ky., to buy a handgun from an owner who had posted an ad on Armslist.com, a controversial online gun marketplace, federal authorities say.
Hendridge, who gave the seller a Kentucky driver’s license bearing his name, paid $220 cash for the 9 mm Taurus pistol, signed a receipt and drove off in a white Dodge Charger, according to court records.
Less than two weeks later, Chicago police acting on an anonymous tip found the same gun hidden in a gangway in a violence-torn neighborhood on the West Side, more than 300 miles away from where it had been sold, according to federal charges announced Tuesday.
The gun was one of as many as 90 firearms purchased through Armslist sellers in Kentucky and trafficked to Chicago before being resold to gang members and drug dealers in the city and suburbs, a 72-page criminal complaint alleged.