Climate Change Theory is on trial in this long-awaited court case. The trial will ask which is more important in America: climate alarmism, or free speech? 

It has taken over a decade to get to court. On one side is Michael Mann, a climate scientist and activist who claims he was defamed in a 2012 blog by writer and broadcaster Mark Steyn.

Ironically, a trial about climate change was delayed by a Washington DC snowstorm. The trial will also put the climate science field and the administration of Penn State University under the spotlight.

Using re-enactments based on actual court transcripts, journalists Phelim McAleer and Ann McElhinney will bring you the day's most dramatic courtroom clashes in the hunt for the truth about one of the biggest issues of our age.