in question vs liable

in question

adj
  • In doubt, under dispute. 

  • Under consideration, under discussion. 

liable

adj
  • likely. 

  • exposed to a certain contingency or causality, more or less probable. 

  • bound or obliged in law or equity; responsible; answerable. 

  • subject; susceptible. 

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