Interview to a student from the states

To present a poster presentation, I interviewed to some people around me.
It was a surprise for me to have a interview wth a student from the states, for a reason as follows:

I asked a question that " If you are taken out your diseased kidney, do you provide it to other patient who want to have kidney transplantation?"to my Dorm mate from the states.
Before the interview, I gave her information that 42 out of 42 case of surgery that Dr. Mannami treated had no problem to the kidney after the transplantation.

I was surprised because I thought she would agree with the diseased kidney transplantation since this method seemed more accepted in the Instates for me, but it was totally wrong. She said, suppose she provides a diseased kidney to other patient and some disease developed to the kidney after the transplantation to the patient. In that case, even if the patient and she have contractual agreements that not to sue her, there is a still chance for her to be sued. Therefore, she said she won’t provide her diseased kidney in any case. While most of Japanese interviewee answered that they will provide their diseased kidney to other, her reason for the answer made me surprised because I haven’t even assume the possibility of lawsuit. This may be a cultural difference.