In this Jan. 23, 2009 file photo, pallbearers carry the casket of 4-year-old Roberto Lopez Jr., outside Our Lady of Angels Church in Los Angeles. The boy was shot in the chest a week earlier as he walked with his 5-year-old sister in a gang-plagued Echo Park neighborhood. In the wake of the Dec. 14, 2012 mass shooting at Sandy Hook Elementary School in the small town of Newtown, Conn., there is now much political discussion about gun control. For urban advocates, this new emphasis on gun control is long overdue.

In this April 1, 2008 file photo, anti-gun literature is displayed in the window of a school bus leaving downtown Chicago after a rally to remember classmates killed by gun violence in the school year and a call for stiffer gun control measures.