Bangladesh, April 26 -- In recent years, jurisdictions such as New York City have expanded policies permitting the involuntary psychiatric evaluation—and in some cases detention—of individuals deemed to pose a potential risk to themselves or others, even in the absence of any criminal act. These policies are often defended as pragmatic responses to public safety concerns, homelessness, and untreated mental illness. Critics typically object on utilitarian grounds (questioning effectiveness or unintended harms) or deontological grounds (invoking individual rights and bodily autonomy).

While these objections are important, they do not reach the deepest ethical problem with preventive detention. What is at stake is not merely the...