"Written on a slab were his name and his crime: REACTIONARY."

This was known as a struggle session

The term Reactionary means one who wants to return to a previous state, usually political. The term was coined in the 20th century to denote a person who opposes the principles of socialism and communism. Often times in socialist or communist countries, it was used as an insult and reason to punish people meaninglessly. Many of these ideas were originally Marxist.