I'll elaborate on the title:
Someone asked me the question:
Do you believe people should be forced to allow the use of their organs without consent?
And in order to respond, I wondered what a court of law in the US would rule in the following scenario:
One day I find myself in the theoretical situation where someone is hanging off the edge of a building and wants to live, and I know with 99.9% surety (lets assume this number is accurate and I admit that I somehow knew this beyond a doubt, for the sake of the theoretical scenario) that if I hold onto them until help arrives, my life won't be at risk, I'll simply have to strain my muscles for an hour until help arrives and they're safe. But I choose to let the person fall to their death, purely and solely because I believe I have the right to decline to use my body in any way I choose not to use it. I do not fear that saving the person puts me in any danger, and I admit this on record - furthermore it's reasonable to believe that that risk assessment is accurate. Also, it would likely be very painful for me to hold onto the person for the hour until help arrives.
Now, in the eyes of a US court, am I a murderer?
Furthermore, if the answer is that I would be considered a murder in the eye of the law, what if we change one detail of the premise: Rather than knowing I have a 99.9% chance of saving the person's life while avoiding any physical or mental damage, that number becomes 90%. Or 80%. Is there any language within the law that specifically defines a threshold beyond which it's reasonable to fear for my health and allow the person to die in order to protect my health?
I realize the answer could vary from state to state, and if you need to use an example state, let's randomly say I'm in California.