I assume the Virginia leaders felt they were handling him fairly, but I don't know of any objective bystanders who believed he was being treated fairly, do you? Certainly the source you posted didn't see it as fair:
The opinion of the towering French poet, novelist, and dramatist Victor Hugo was judged by many to be the verdict of the civilized world. He strongly opposed the punishment. Many in Europe followed Hugo's lead in their disappointment that America chose to execute a man for only trying to free slaves.