Former Rep. Gabby Giffords and her husband, Mark Kelly, at a gun show in Saratoga Springs, N.Y., in October. Giffords was shot in the head in a 2011 mass shooting in Tucson. She and Kelly have since founded a political action committee to push for tougher gun laws. Tim Roske/AP hide caption

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An image from a Connecticut State Police report on the shootings at Sandy Hook Elementary School shows a scene at 36 Yogananda St. in Newtown, Conn., where Adam Lanza killed his mother before driving to the school and killing 26 students and staff last December. AP hide caption

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Voters in Newtown, Conn., have approved a plan to use nearly $50 million in state funds to demolish Sandy Hook Elementary and build a new school in its place. This photo provided by Craig Hoekenga shows his son Trey, a kindergarten student at Sandy Hook, on the school bus this year. The window has a quote from the late principal, Dawn Hochsprung, who was killed in last December's mass shooting. Craig Hoekenga/AP hide caption

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Francine Wheeler, seen here delivering the presidential address alongside her husband, David, urged the Senate to pass gun control legislation. YouTube 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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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

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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

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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

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Mourners leave the Honan funeral home after attending the funeral of Jack Pinto, 6, one of the victims of the Sandy Hook Elementary School shootings, in Newtown, Conn. Emmanuel Dunand/AFP/Getty Images hide caption

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President Barack Obama speaks at a memorial service for victims of the Sandy Hook Elementary School shooting. "I come to offer the love and prayers of a nation," he told the crowd in Newtown, Conn., Sunday. Mandel Ngan/AFP/Getty Images hide caption

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State Police officers pass a makeshift memorial as they respond to a threatening phone call that caused the evacuation of St. Rose of Lima Roman Catholic Church in Newtown during Sunday services. Mario Tama/Getty Images hide caption

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On a hillside in Newtown, Conn., art teacher Eric Mueller sets up wooden angels in memory of the victims of the Sandy Hook Elementary School shooting. Details about the lives of the slain are showing the depths of the community's loss. Emmanuel Dunand/AFP/Getty Images hide caption

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