Michael Bloomberg; Newtown School Shooting; Castro Brothers

New York City Mayor Michael Bloomberg advocates for stricter gun control laws in the aftermath of the Sandy Hook shooting in Newtown, Conn. Richard Aborn of the NYC Citizens Crime Commission, CBS reporter John Miller, and Dr. Jeffrey Lieberman describe the profile of the Newtown shooter and also argue for more stringent gun laws. Twin brothers Joaquin Castro, representative-elect from Texas, and Julian Castro, mayor of San Antonio, reflect on the influence of their upbringing on their rising political careers.