I think that's a good thought. You're right when you say that because of passwords on phones, these people died. But I don't agree that this kind of method (having no password) is the right one. One some phones you don't have the possibility to secure your photos. On my phone (I just tried it), you can push an emergency call button to phone the police or the ambulance. It's an iPhone 6. You don't have to put in the code.