clemency vs compassion

clemency

noun
  • The gentle or kind exercise of power; leniency, mercy; compassion in judging or punishing. 

  • A pardon, commutation, or similar reduction, removal, or postponement of legal penalties by an executive officer of a state. 

compassion

noun
  • Deep awareness of the suffering of another, coupled with the wish to relieve it. 

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