Wesley Smith, JD, Anti-Euthanasia Activist, wrote in his 1997 book Forced Exit:

“Living wills negate informed consent. Since no one knows the future, by definition their care or noncare instructions must generally be written. Thus, when an incapacitation occurs, the patient’s feelings and desires about this specific circumstance may not be known. The living will puts tremendous power into the hands of doctors, who are empowered to decide whether and when the living will takes effect, when treatment should be withdrawn or withheld. Moreover, the decision regarding the type and extent of medical intervention to be withheld is the doctor’s. And this power isn’t restricted to ‘extraordinary care’ such as ventilators to assist with breathing, but to any medical intervention–from not treating a curable bacterial infection to withdrawing food and fluids so that the patient starves and dehydrates to death. Thus, with a living will, the check of informed consent is surrendered to medicalized decision making.