When I was CPR certified we were told that we were obligated to try to give aid. That meant that we were obligated to call 911.
Perhaps that's what I'm thinking of.
I was always instructed that if you BEGIN
providing CPR, you were obligated to continue until relieved by a Doctor/EMT/Paramedic, or by another CPR certified person. As a person who is not medically licensed, you are not capable of making the determination on your own whether or not it is safe to stop providing CPR. You are under no obligation if you never begin providing CPR.
This incident happened in my town, and just down the road from where I live. From the articles I've seen on the local news and in the local paper, the family very much wants this issue put to rest and is adamant that this is what their mother would have wanted. I feel we should respect their wishes.