Shock, frustration surround shootings of NYPD officers

Aired: 12/21/2014 | 0:03:11 | Clip
As the investigation into the two New York Police Department officers who were fatally shot over the weekend unfolds, shock and frustration prevail. The incident tops off months of nationwide demonstrations against police and a public fallout between New York City's mayor and the police union. NewsHour's William Brangham reports.