authorization vs free speech

authorization

noun
  • (A document giving) formal sanction, permission or warrant. 

  • Permission. 

  • Permission, possibly limited, to spend funds for a specific budgetary purpose. 

  • An act of authorizing. 

free speech

noun
  • Expressions that are or should be allowed in some moral or legal context. 

  • The right to express an opinion in public without being restrained or censored. 

How often have the words authorization and free speech occurred in a corpus of books? (source: Google Ngram Viewer )