Wooden angels memorialize the victims of Adam Lanza's shooting spree in Newtown, Conn., last December. An upcoming Frontline documentary seeks to provide new details about Lanza and his mother, Nancy. Emmanuel Dunand/AFP/Getty Images hide caption

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Neil Heslin brought a framed photo of himself and his son Jesse (when the boy was an infant) to Monday's hearing in Hartford, Conn. The 6-year-old was killed at Sandy Hook Elementary School in December's shooting. Cloe Poisson/Hartford Courant /MCT /Landov hide caption

itoggle caption Cloe Poisson/Hartford Courant /MCT /Landov

This photograph of Aline Marie praying outside St. Rose of Lima church in Newtown, Conn., has become the focus of a conversation surrounding ethics and photography on NPR's Picture Show blog. Emmanuel Dunand/AFP/Getty Images hide caption

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President Obama, accompanied by Vice President Joe Biden, talks at the White House on Jan. 16 about proposals to reduce gun violence. Obama has called for a ban on military-style assault weapons and high-capacity ammunition magazines and is pushing other policies in the wake of the mass shooting last month at an elementary school in Newtown, Conn. Charles Dharapak/AP hide caption

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Early Thursday morning, a school bus carrying students from Sandy Hook Elementary headed to their new school. Timothy A. Clary/AFP/Getty Images hide caption

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The Journal News' map of gun owners in Rockland County, N.Y. At its website, the image is interactive so that users can see who has handgun permits and where they live. The Journal News hide caption

itoggle caption The Journal News

Remembering the victims: Earlier this month, two mourners paused at a makeshift memorial in Newtown, Conn., for the children and adults killed at Sandy Hook Elementary School. Zhang Chuanshi /Xinhua /Landov hide caption

itoggle caption Zhang Chuanshi /Xinhua /Landov

After the attack: Balloons hung from the Sandy Hook Elementary School sign on Dec. 15. On Dec. 14, six adults and 20 children were killed there before the gunman took his own life. Shannon Stapleton/Reuters /Landov hide caption

itoggle caption Shannon Stapleton/Reuters /Landov

A person's DNA can say a lot about a person, but not why someone has committed a horrific crime like mass murder. iStockphoto.com hide caption

itoggle caption iStockphoto.com

Stuffed animals and flowers at a makeshift memorial near the entrance to the grounds of Sandy Hook Elementary School. Brendan Smialowski /AFP/Getty Images hide caption

itoggle caption Brendan Smialowski /AFP/Getty Images

A Sig Sauer handgun on sale at a shop in Tucker, Ga. Erik S. Lesser /EPA /LANDOV hide caption

itoggle caption Erik S. Lesser /EPA /LANDOV

A woman and child earlier this week at a makeshift memorial in Newtown, Conn. Shannon Stapleton /Reuters /Landov hide caption

itoggle caption Shannon Stapleton /Reuters /Landov

U.S. Marine Corps Reserve Sgt. Craig Pusley stood guard Wednesday at Hughson Elementary School in Modesto, Calif. Ed Crisostomo /MCT /Landov hide caption

itoggle caption Ed Crisostomo /MCT /Landov

A child peers through firefighters standing as the procession heads to the cemetery outside the funeral for school shooting victim Daniel Barden at St. Rose of Lima Catholic Church in Newtown, Conn., Charles Krupa/AP hide caption

itoggle caption Charles Krupa/AP