The ‘Slippery Slope’ of Euthanasia

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One of my favorite parts of getting around Washington, D.C. is the Metro system. The zzzip of the Metro fare card that opens the turnstile, the flashing lights that announce the incoming train, and the garbled announcements of the upcoming station create a vivid collage. Even more, the long entrance/exit rides, such as on Rosslyn station’s 270-foot escalator, induce a bit of vertigo. The wide stainless steel divider might tempt brash or drunk riders to emulate their childhood prowess on the playground slide, but large discs mounted at strategic intervals along the divider deter all but the most foolhardy. It is dangerous to descend that slippery slope.

As many of us are well aware, the “slippery slope” image is also a kind of argument, one that is usually dismissed out of hand. The basic idea is this: If doing X is not bad or wrong, but by permitting X we must also permit Y, and Y is wrong, then we should not permit X. Although X is not bad in and of itself, reason tells us that it will lead to Y. The proponent of the argument may marshal evidence to show that X is a causal link to Y, or that it is linked to Y as a probability.

The slippery slope argument is often rejected as fallacious when the proponent fails to introduce evidence or warrants that support the conclusion that X leads to Y. This one-thing-leads-to-another argument is reminiscent of the “camel’s nose under the tent” image, or the “if you give a moose a muffin” children’s story. The argument is rejected because of the piling up of increasing improbable probabilities, or the extreme nature of Y.

This is not to say that the slippery slope should never be employed. There are times when X does lead to Y. Recently, bioethicist Art Caplan admitted that the euthanasia slope was indeed slippery. It wasn’t that long ago that Caplan favored legalization of assisted suicide with “careful regulation.” Euthanasia would be limited to people with a terminal illness and intractable pain.

Yet, in an August 2015 commentary, Caplan and co-author Barron Lerner questioned whether euthanasia might not indeed be on a slippery slope. Addressing the notable increase in euthanasia deaths in Belgium and the Netherlands, Caplan wrote of his discomfort in expanding euthanasia to people who were healthy but sad or grief stricken.[1] The assisted suicide rate in Belgium more than doubled in 2013, increasing from about 2% to almost 5% of all deaths, with an increase in the Netherlands to 3.3% of all deaths.[2]

The initial reasons given for speeding up death soon expanded to physical suffering without hope of improvement (not necessarily terminal illness), loneliness, and being “tired of living.” Doctors in Belgium and the Netherlands have hastened the death of people who are depressed, or distressed over the results of sex change surgery; who have autism, blindness, anorexia, chronic fatigue syndrome, schizophrenia; and who are dependent upon others for care.

A similar expansive slide occurred among the people included: first, only adults could consent. Then, babies were added to the list (with parental consent). Next, children ages 12–16 were deemed able to choose assisted suicide, again with parental consent. Not surprisingly, pediatricians are now arguing that the law discriminates against the child of eleven years and nine months, and that no child’s age should disqualify them from a physician-assisted death. At the bottom of the slippery slope are real people, those who are old, poor, disabled, minorities, and people with psychiatric impairments.

These scenarios were predicted by opponents of assisted suicide and euthanasia of patients who did not or were unable to consent. Hindsight and the data provided by Belgium and the Netherlands confirm that the trajectory of opening the door to assisted suicide is indeed a downward, slippery slope. Caplan does not think the European experience will cross the Atlantic, yet we have seen legalized physician-assisted suicide expand from Oregon to include Washington, Vermont, Hawaii, Colorado, the District of Columbia, Montana, and most recently, California.

The road to euthanasia begins at our northern border. More than 2,000 Canadians have died under Canada’s 2016 “Medical Assistance in Dying” law. Of the reported cases, only five deaths were “self-administered,” which leads to the conclusion that the others died at their doctor’s hand.[3] Why? Because the patients cannot do it “properly” and complications occur.

Other bioethical arguments reflect the kind of wisdom that may be veiled within a “slippery slope” argument. The law of unintended consequences comes to mind, along with the precautionary principle. Because it is so difficult to reverse course, prudence dictates circumspection. (This is not a tacit acceptance of the original approval of euthanasia; I am making a more general point about permitting that which was previously forbidden or restricted.) Of course, it is good news when prominent bioethicists publicly admit that some slopes are indeed slippery, and that “part of the problem with the slippery slope is you never know when you are on it.”[4]

The moose’s muffin and the camel’s nose are not simply images. They depict the reality that disastrous outcomes can ensue from seemingly benign, small beginnings.[5] And, in the current undermining of care for the vulnerable, unlike the Metro escalator discs designed to prevent sliding, there appear to be few obstacles to a drastic expansion of whose death should be speeded along. While the concerns about endless expansion of assisted suicide are valid, there is a more serious problem. We must reject the underlying premise that X—a “good death” for a few—is good for anyone. The rush toward physician-assisted suicide is an “escalator” no one should be riding.


[1] Barron Lerner and Arthur L. Caplan, “Euthanasia in Belgium and the Netherlands: On a Slippery Slope?” JAMA Internal Medicine 175, no. 10 (2015): 1640-1641.

[2] Raf Casert, “Study: Euthanasia Cases More than Double in Northern Belgium,” AP News Archive, March 17, 2015,

. Cf. Winston Ross, “Dying Dutch: Euthanasia Spreads across Europe,” Newsweek, February 12, 2015,

[3] Kathleen Harris, “More than 2,000 Canadians Have Died with Medical Assistance since Legislation,”, October 6, 2017.

[4] Lerner and Caplan, “Euthanasia in Belgium and the Netherlands,” 1641.

[5] I have borrowed “small beginnings” from Leo Alexander, the chief medical consultant at the Nuremberg War Crimes Trial, who noted that “Whatever proportion these crimes finally assumed, it became evident to all who investigated them that they had started from small beginnings.” Leo Alexander, “Medical Science under Dictatorship,” New England Journal of Medicine 241, no. 2 (1949): 44.