Clive this is a very good question for people to look into. And the answer is a resounding Yes!
Anyone can be "charged" for about any conceived notion of the violation of a criminal statute.
There is a young man sitting in a jail for a year for taking an innocent picture of the submarine he served on, for nostalgia sake. 2 kids and a wife now on welfare. He never showed them to anyone but family. So he was charged and convicted.
We all know what Hillary did -- no charges?
With that said. Yes they could be convicted if they were in such a position of control over the killer. Think brainwashing, drug control, parent and young child. Remember Jim Jones? Karesh? Threatening and having the means to kill a child. Then in some states having a party and letting a drunk guest drive to their death.
I like to use it as a metaphor for someone who is harmed by feeling guilty about something. They charge themselves with their "crime" but never get a trial.