come down on (like a ton of bricks) vs exonerate

come down on (like a ton of bricks)

exonerate

verb
  • To free (someone) from an obligation, responsibility or task. 

  • To free (someone) from accusation or blame. 

How often have the words come down on (like a ton of bricks) and exonerate occurred in a corpus of books? (source: Google Ngram Viewer )