Family members of those killed in the Newtown, Conn., school shooting stand together as President Obama speaks at the White House on Wednesday, after gun control measures were defeated in the Senate. In the foreground are Mark and Jackie Barden with their children Natalie and James, who lost Daniel. Behind them are Nicole Hockley, mother of Dylan, and Jeremy Richman, father of Avielle. Carolyn Kaster/AP hide caption

itoggle caption Carolyn Kaster/AP

A Bushmaster rifle, similar to the type used by Adam Lanza during the shooting at Sandy Hook Elementary School, and some ammunition magazines. The sale and possession of this type of weapon, and high-capacity magazines, will be severely restricted in Connecticut under new legislation. Michelle McLoughlin /Reuters /Landov hide caption

itoggle caption Michelle McLoughlin /Reuters /Landov

Dec. 18, 2012: Crime scene tape stretches across the property outside the home where Adam Lanza lived with his mother, Nancy Lanza. Inside, police found weapons and other evidence. Lucas Jackson /Reuters /Landov hide caption

itoggle caption Lucas Jackson /Reuters /Landov

Some of the many cards, letters and artwork sent to Newtown from all over the world was on display at the Newtown Municipal Center on Jan. 30. The items were recently moved to temporary storage. Courtesy of Ross MacDonald hide caption

itoggle caption Courtesy of Ross MacDonald

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

itoggle caption Timothy A. Clary/AFP/Getty Images

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

Mourners put decorations on a Christmas tree, part of a memorial in Newtown, Conn. Holiday greetings, toys and cards have flowed into the town, and some residents say the community feels closer-knit since the shooting. Zhang Chuanshi /Xinhua/Landov hide caption

itoggle caption Zhang Chuanshi /Xinhua/Landov

Christmas stockings with the names of shooting victims hang from a railing in the Sandy Hook village of Newtown, Conn. Julio Cortez/AP hide caption

itoggle caption Julio Cortez/AP

Police Lt. Ray Mesek registers a rifle at a gun buyback event on Saturday in Bridgeport, Conn. Spencer Platt/Getty Images hide caption

itoggle caption Spencer Platt/Getty Images

A school bus drives past a welcome sign near the Chalk Hill Middle School in Monroe, Conn. Students from Sandy Hook Elementary in neighboring Newtown will attend the school in January. Lucas Jackson/Reuters/Landov hide caption

itoggle caption Lucas Jackson/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