besmirching vs spoliation

besmirching

spoliation

noun
  • Robbery or plunder in times of war; especially, the authorized act or practice of plundering neutrals at sea. 

  • The intentional destruction of or tampering with (a document) in such way as to impair evidentiary effect. 

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