All physicians may not feel comfortable volunteering to help in a possible medical emergency-- for example, a non-practicing physician who is involved primarily in research, or a physician in a specialty that has not thought about emergency medicine in decades. I'm not sure what the liability is if a physician volunteers his/her services when he/she is not really qualified to provide assistance and the outcome is negative-- this could possibly considered malpractice since the physician is outside his/her scope of practice.