condone vs sign off on

condone

verb
  • To forgive, excuse or overlook (something that is considered morally wrong, offensive, or generally disliked). 

  • To allow, accept or permit (something that is considered morally wrong, offensive, or generally disliked). 

  • To forgive (marital infidelity or other marital offense). 

sign off on

How often have the words condone and sign off on occurred in a corpus of books? (source: Google Ngram Viewer )