Free speech: Science or ideology?

There is a phrase in the video about judges and juries, when hearing technical, scientific arguments, might make decisions based on popular beliefs rather than science.  This is how the court of public opinion and government operates today.  Free speech needs to be protected so that no matter the topic, no matter what side one is on, the truth can be told.
  
Opinion Journal:
Is Questioning Climate Change Illegal? 
Wall Street Journal November 25, 2014   
Video interview.
  
Author Mark Steyn explains why Penn State climate scientist Michael Mann is suing him for alleged defamation.