Scholars explore the documented discusions about what books would be placed on the Index – or not.

When he received special permission in 1992 to be one of the first historians to see the secret documents of the Index, they were jumbled and there was no catalogue. In 1998, the Vatican officially opened the complete archive to historians.

The 19th century findings have already been published in the form of complete listings and other scholarly works of reference.

The objective remains to compile a complete survey from the 16th century to 1967, when the modernized church recognized that freedom of conscience was a greater good than supervising reading habits.