Some were written by former and current patients, others by concerned psychiatrists such as the dissident physician Semyon Gluzman, pictured.

They were passed around in secret because even possession of such material might taint their owners as ‘inakomysliashchie’ – differently-thinking people who shared the authors’ dissenting frame of mind, a dangerous position to find oneself in the Cold War-era USSR.

Using false diagnoses of mental ill-health as a punitive measure was not a new way of weaponising the state apparatus against its own people, but it did run directly counter to promises of reform made by Khrushchev and others who sought to distance themselves from Stalin’s brutality.

By 1959, Khrushchev had decreed in a speech to the Union of Soviet Writers: “A crime is a deviation from the generally accepted norms of behavior in society, often caused by mental disorders.

“Can there be diseases, mental disorders among certain people in a communist society? It appears there can be. If so, then there can also be offenses that are characteristic of people with abnormal minds.”