Religious Beliefs on Trial?

Read this article. Due to the potential religious and political ramifications I’ve been following this case with a lot of interest. In summary, the state’s case here is that Mitchell has to be psychotic because he believes that God speaks to him. In my mind that pretty much leaves the door open to declare that anyone with religious beliefs can be declared incompetent to stand trial and be force medicated in order to receive a “fair” trial.
Please note that my remarks should in no way be interpreted as a defense of Mitchell's criminal actions against Elizabeth Smart. We just need to be sure that it is his actions that we procecute and not his beliefs which triggered them.