exculpation vs exoneration

exculpation

noun
  • The act of exculpating from alleged fault or crime. 

  • That which exculpates; an excuse. 

exoneration

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

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

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