Psychiatry

In the Soviet Union, systematic political abuse of psychiatry took place. Psychiatry of the Brezhnev period was used as a tool to eliminate political opponents ("dissidents"), people who openly expressed their views that contradict officially declared dogmas. In case the person did not agree with the specific actions of people in leading positions and criticized them by using philosophic dogmas according to the writings by Karl Marx,Friedrich Engels, Vladimir Lenin, the term "philosophical intoxication" was widely used to diagnose mental disorders.In such cases, religious faith was determined to be a form of mental illness that needed to be cured.

"...there was no other logical rationale why one would oppose the best sociopolitical system in the world"

http://en.wikipedia.org/wiki/Political_abuse_of_psychiatry_in_the_Soviet_Union