Helaman 8
The appearance of boldness among the wicked is generally a sham – in truth, the vast majority of wickedness is perpetrated as a matter of cowardice, either bowing to the pressure of those around them, or at least seeking some sign of approval or acceptance before leading the way into greater sin than is already apparent.
I believe that as Nephi was preaching he only was given the knowledge of the murder of the chief judge less than one minute before he declared it to the crowd. It is interesting to think that he had been their chief judge less than ten years earlier.