http://mediamatters.org/blog/2017/01/24/donald-trump-sean-spicer-and-george-costanza-rule-lying/215108
"Spicer doesn't want reporters calling him a liar because that would make it impossible to do his job. And he definitely wants to ensure that they don't use that terminology to refer to President Trump. So he used his first press briefing to claim that his statements aren’t lies if he believes them."
