Anonymous gun buy back program

Guns sit on a table that were surrendered during a gun buy back program on Dec. 15, 2012, in San Francisco, Calif. The San Francisco Police Department held a one-day gun buy back event that paid $200 per gun turned in. A better than expected crowd resulted in payback money running out and vouchers were issued to collect money within a week. Over 200 guns were collected.

Credit: Justin Sullivan/Getty Images