Unfortunately.
Damnable government interference in personal business.
So9
Suppose you're incapacitated and an heir shows up with a "living will" that says you want to be starved to death. The will happens to resemble their handwriting much more strongly than yours. Should a court accept the document at face value, or should it allow examination of its authenticity?
Outlawing "assisted suicide" falls well withing a legitmate reason -- the MOST legitmate reason -- reason for founding any government. That is: to protect the weak and otherwise helpless.
Liberty first requires life. To preserve the freedom to contract, to trade and to own property, we must first protect the lives of the weak from the brutish. Otherwise the brutish take all other liberties away.