Chief judge is the only one with clear mind here. Arata is starting to believe that Shinju is innocent and wants to protect and stay by her side. How stupid can you get. Even though she is not guilty, this is typically a white knight syndrome shown by Arata.
Some people are attracted to others they deem to be “broken” because they want to “fix” them—this is known as white knight syndrome. This is someone metaphorically riding in on their white horse and saving you from the evil dragon. That's what's happening.