Actually, they pleaded not guilty from the start and said they did not start the fire. Why is there supprise with the details of their story of innocence when it was their claim from the beginning? Does "smelling of lies" equal telling lies, and if so, what lies is the defense lawyer telling? 
If you know what happened for certain go testify. If you don't let the trial play out. Maybe they really didn't do it. Me personally, I have no clue as to their guilt. I have not seen the evidence or listened to the testimony. So I will let the legal process make the call.