There have been few cases where somebody with a sleeping disorder actually killed somebody while sleepwalking. And the law says this is not punishable because the person had no recollection of what they were doing and had no control over it. First you have to understand what sleepwalking is. There are two phases to sleep: the deep sleep and the dream sleep. For some unknown reason, sleepwalkers cannot transition to the dream sleep properly. It [b][u]is[/u][/b] a neurological disorder. Experts say that stress and lack of sleep can cause it. Experts also say that the brain is still half asleep while sleepwalking. Certain parts of the brain simply don't function. Its theorized that sleepwalkers cannot recognize faces even if they're familiar ones; they are unable to think with logic; they are unaware of day and night; and they experience strong "flight or fight" instincts, which is the dangerous part. Say somebody was stressed out that their car broke down. They end up sleepwalking that night and went to the garage and tried to fix it. This is their only goal at mind and they usually try to accomplish their goal without anything or anyone getting in their way. If you were to get in the way of this sleepwalker and didn't want him to attempt to fix his car, his "fight or flight" instincts will kick in and may end up resulting in violence. The law says you cannot be convicted for killing someone if it was proven you were sleepwalking at the time. And it does need to be proven just like anything else in court. You can't just walk up to the stand and say "I was sleepwalking" without any evidence. But is this really justifiable? Yes, you didn't have any control over your actions...but you still took the life out of a person, possibly even a completely innocent one too. Maybe one that you even loved. Maybe that's punishment of its own, knowing that you took the life of someone you cared about.