Legal provisions on medical aid in dying encode moral intuition.

In recent decades, many jurisdictions have moved toward legalizing euthanasia and assisted suicide, alongside a near-universal increase in public acceptance of medical aid in dying. Here, we draw on a comprehensive quantitative review of current laws on assisted dying, experimental survey evidence, and four decades of time-series data to explore the relationship between these legislative transitions and change in moral attitudes. Our analyses reveal that existing laws on medical aid in dying impose a common set of eligibility restrictions, based on the patient's age, decision-making capacity, prognosis, and the nature of their illness. Fulfillment of these eligibility criteria elevates public moral approval of physician-assisted death, equally in countries with (i.e., Spain) and without (i.e., the United Kingdom) assisted dying laws. Finally, historical records of public attitudes toward euthanasia across numerous countries uncovered anticipatory growth in moral approval leading up to legalization, but no accelerated growth thereafter. Taken together, our findings suggest that the enactment of medical aid in dying laws, and their specific provisions, crystallize patterns in moral intuition.