, director of Annenberg Political Fact Check
, discusses the latest whirl of rumor and truth affecting both candidates.
Paul Ekman, director of the Paul Ekman Group, discusses facial expressions to detect lying in politicians.
Fred Melo, public safety reporter with
St.Paul Pioneer Press, talks about protests at the Republican convention.
Nate Silver, founder of fivethirtyeight.com, analyzes the week's events at the Republican convention.