Psychiatric imprisonment is involuntary imprisonment of people on the grounds that they are considered psychiatrically insane. In many countries, people behaving in such a way considered insane by a local judge can be put into a mental institution without trial. Critics argue that an open society based on freedom and personal responsibility has no room for treatment of this nature.
In some countries, activities such as homosexuality and adultery can result in such imprisonment. In others, such as the defunct U.S.S.R, and some claim China, Canada and the U.S.A, amongst others, such hospitals are routinely used to imprison dissidents.
Dr. Thomas Szasz argued that while these practices may have begun as an alternative to punishment, specifically retributive justice, in the U.S.A. they had become by the 1960s a means of defining mere differences as illnesses. This view has become much more prevalent and is today common among even the psychiatric profession, which views itself in a harm reduction role, and feels that psychiatric imprisonment is a legacy system that has no longer any clear moral justification.