arraignment vs exoneration

arraignment

noun
  • The formal charging of a defendant with an offense. 

exoneration

noun
  • The state of being disburdened or freed from a charge. 

  • An act of disburdening, discharging, or freeing morally from a charge or imputation. 

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