Organ donation today is an opt-in system - People have to assert that they want to be organ donors.
Proposed - Make organ donation an opt-out system, e.g., you are an organ donor unless you specify otherwise.
A person would have the right to specify
a) whether they want to opt out of organ donation,
and they choose to be an organ donor,
b) one of several degrees of death (brain death, permanent loss of consciousness, etc.) that medical staff would determine they had reached before harvesting organs
The default degree of death might be brain dead.