Aviation's excellent safety record has only been achieved because people are willing to admit their mistakes without fear of the Police knocking on their door.
As soon as you introduce phrases such as 'criminal negligence' for what passes as human error - or even human stupidity - our industry will move backwards. It's why we have ASRs, MORs and safety bulletins - to learn from others' mistakes and to publicise our own errors without fear of prosecution.
The system seems to have worked in this case. Introduce prosecution and you introduce cover-up and conspiracy.