Watch the prank here: http://www.youtube.com/watch?v=7N5OhNplEd4
Do you think the person responsible should be criminally liable for that?
What do you mean by "criminally"?
No, but perhaps the victims should be sued for stupidity.
A ghost? Really? Even when people see supposed 'real' ghosts, they never look that solid and that cohesive.
I'm not totally sure how it works, but I would guess that before the "victims" of the prank get on camera, they probably have to sign some sort of waiver that says they agree to participate (like all reality shows), even if they aren't told exactly what will happen. Otherwise, can you imagine the lawsuits if an unsuspecting person has a heart attack and dies from the prank? You probably can't just pull people off the street and put them in a situation where they might die of fright.
If no contract is signed, yes I think in the event of a heart-attack or similar complication purposely causing intense emotional distress should make you liable.
The other liability question that occured to me watching this video is whether or not the people being pranked should have been liable if they had attacked the little girl, especially while she was screaming.
What your talking about is a tricky issue from a libertarian standpoint for sure.
On one hand things like this can cause real and physical harm to a person, so it could be thought of as initiation of violence.
On the other hand the individual is not physically doing anything and almost certainly has no way of knowing that what they do will cause this reaction. It brings up a very unclear line as well. At what point can we say or not say a person has caused someone else harm?
I think that most would have to agree then that things like this can't be considered a breach of the NAP.
When I was 5 or 6 I remember going with my Dad to a bunch of tourist shops at the Lake of the Ozarks, there was a little shop (really just a closet) called "Betty's Boarding House" with a dark window. Upon opening the door a fake skeleton shoots out at your face screaming. I've never been so scared in my life, I took off running backwards, flipped over a park bench fell and kept running away on my knees. I could very easily have run out into traffic. While I still find it funny, there definitely should be some liability.
I remember it being gone for years and heard it was because someone had a heart attack. Then it was back again, no idea if it's still there, but I found nothing searching the web.
Don't really have anything to add to the thread, it was just fun to remember.