@blueveinedthrobber,
Depends on what state you're in. Some states make it a crime for a bystander to fail to render assistance in certain cases. For example,
Washington says that, if you witness someone being injured in a crime and do nothing about it, you're guilty of a misdemeanor. I think a few other states have similar laws. Most, however, do not, and the general rule in Anglo-American law has always been that a bystander has no positive duty to render aid or assistance to an injured person.