escape clause vs escape route

escape clause

noun
  • Any clause, term or condition in a contract or statute that avoids the application of a provision 

escape route

noun
  • A way out of a difficult or unpleasant situation. 

  • A path used by someone to escape from a dangerous place. 

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