Just make it so only the person or a personally appointed representative of that person can make the call, no exceptions.
And even at that, there is potential for abuse - someone making the call against the person's wishes, or for their own personal gain. But you can not eliminate that possibility entirely, and when something like that happens - it's murder in my book.
This is a subject that is very close and personal to me. As we speak, my mother languishes in a nursing home having suffered from Alzheimer's for nine years now. She has been institutionalized for the last four years. We kept her at home as long as it was possible, but she requires 24 hour care as she can do NOTHING for herself. She speaks very little now, in very low tones and none of it makes any sense.
When she was well, we talked many times about what we would want in case of being diagnosed with a terminal illness. She made it clear that she didn't want her life prolonged artificially, or if there was no hope of recovery - she didn't want extraordinary means being taken to extend her "suffering". She was a Christian and told me she wasn't afraid to die.
The problem is that she was talking about getting cancer or something like that - where she would be clear enough of mind to decide when the time would come for her to choose death. Never once did we talk about a mental condition like Alzheimer's. She descended into her hell so slowly that by the time we all realized it, she couldn't communicate to us about it.
Now, my father has the same thing - we're keeping him at home as long as possible - but eventually I won't be able to care for him as he will need.
My mother is virtually dead - the woman that is that person is gone. Yet she languishes.....they check her blood sugar all the time, give her insulin when she needs it....give her morphine for her pain....feed her every bite of mashed food that she eats....bathe her and dress her. Why? Is this living? Is this the existence my mother would want to endure? When she can pass through these mortal bonds and join her heavenly Father in eternity? I look in her eyes and I see a tormented soul trapped in a useless body that is shutting down bit by bit. Yet - to great expense - they keep her alive....like some kind of Frankenstein thing.
Do I want my father to end up in the same situation? No way. I hope he dies of natural causes in his home before we are faced with that ordeal again. My father, on the other hand is of a fighter mentality and would never agree to ending his own life. He has told me so and if able to decide himself - would want any means feasible to prolong his life.
Because of my up close and personal experience with this, my feelings about nursing homes and such are that they are in many instances a cruel alternative to death. If you still have your mind and can enjoy the activities of socializing, bingo, television etc - yes, a nursing home is good for people that cannot stay in their homes. But if your brain is shrinking, there is no cure, and you face possibly years of losing your cognitive abilities followed by the gradual shutting down of your body - unable to recognize your loved ones, unable to move about - even unable to watch tv - only to start to shrivel and contract as your muscles, and then your organs, start to shut down bit by bit...........................................why in the hell keep someone like this alive with medicines and such? It is cruel and inhumane in my book..............and I wish I could have helped my mother end her life before they took over her destiny in the nursing home. I know she would have wanted that.
I was with my mother-in-law in the hospital the night she died from cancer. She had been in horrific pain and the morphine was making her have horrible hallucinations of monsters and things. She was so agitated and just writhing that night. Then she passed and finally there was peace in her face. It was an experience I will never forget.
I do not fear death. I wish there was a way I could help my parents not have to endure this prolonged death that modern medicine has inflicted.