'Merchants Of Doubt' Explores Work Of Climate Change Deniers

NPR's Melissa Block speaks to director Robert Kenner about his documentary, "Merchants of Doubt," which examines the work of climate change skeptics and their campaign to sway public opinion.
Interview:
http://www.npr.org/2015/03/06/391269315/merchants-of-doubt-explores-work-of-climate-change-deniers