What? Who me? I'd break the little fvcks neck before he even knew I was next to him.
I'd hope grannie would enlist my help, though.
Still, people do funny things under stress.
And it would help a subsequent investigation if some pictures of him (or her) got mailed out before anything noisy happened.
Oh, so you want to take pictures. Well, just think about that mother next to you. Maybe she wants to raise her kids and wants to get out of there alive.
Maybe you could just carry a polaroid camera and solve the whole thing. You get to take your pictures and the co-riders get to live another day.
Man, I should be a homeland security worker.