Bastarache examined the meaning of a mental disorder. He identified two approaches under section 16. First is the "internal cause" theory in which the judge compares "the accused's automatistic reaction to the way one would expect a normal person to react in order to determine whether the condition the accused claims to have suffered from is a disease of the mind." This takes into account the triggering event, and whether a normal person might have entered into an automatistic state. For example, an extremely shocking event would reasonably turn someone automatistic.