In medicine, that dilemma arises only among patients whose choice to end life is motivated by the understandable desire to escape untreatable physical pain or discomfort.

In some cases, it is not necessarily pain per se that the patient, but physical or cognitive debilitation that patients wish to escape by authorizing their physicians to end their lives painlessly. Typically, Dr. Kevorkian's patients suffered from incurable illnesses and congenital diseases that caused them more pain than they wished to endure until their natural death. All of Dr. Kevorkian's patients suffered from incurable conditions that either caused continual physical pain that could not be relieved by any medical treatment or they wished to avoid a tremendously uncomfortable death, albeit by "natural causes," such as by slow suffocation from gradual paralysis of their respiratory function at the end stage of disease (Humphry, 2002; Martindale, 2007).

In the modern age of medicine, the arsenal of treatment modalities undeniably provides tremendous benefits to millions of people, the overwhelming vast majority of whom would gratefully welcome additional years of life made possible by medical science. Unfortunately, in a comparatively few cases, medical treatment that is perfectly routine in the modern medical era increases pain and suffering if the patient is deprived of the right to decide how much pain and/or debilitation is too much to endure. The "luckiest" of those patients need only refuse medical treatment that is necessary to prolong life. However, for the suffering patient whose medical health is "stable" from a clinical perspective, there is no legal right to solicit the assistance of physicians to end life.

While secular law in the U.S. should no longer incorporate any moral definitions of religious origin, it is...

Modern secular legislators should employ similar reasoning in the case of exceptions to the general rule that human life is precious, simply because from the point-of-view of the individual suffering from constant pain, escape from pain may be valued much more preciously than mere continuation of life.
Conclusion:

In principle, logically sound criteria for respecting the patient's right of privacy and personal autonomy should include untreatable persistent physical pain, impending loss of cognitive function or even physical function, or a medical prognosis of a painful "natural" death. In many respects, secular laws that prohibit physician-assisted suicide may actually violate the most fundamental function of medicine in the modern era: namely, to treat pain and physical discomfort. In fact, it may be the very narrow definition of the concept of harm that accounts for the apparent inconsistency of physician-assisted suicide in the modern medical era and the ancient Oath to "do no harm."

References

Humphry, D. (2002). Final Exit: The Practicalities of Self-Deliverance and Assisted Suicide for the Dying. Junction: Norris Lane Press.

Levine, C. (2008). Taking Sides: Clashing Views on Bioethical Issues 12th Ed. Dubuque Iowa: McGraw Hill.

Martindale, M. (2007). Kevorkian: Jail Reform Is His New Cause. The Detroit News, August 8/07.

Tong, R. (2007). New Perspectives in Health Care Ethics: An Interdisciplinary and Cultural Approach. Upper Saddle River, NJ: Pearson.