blameless vs clean as a hound's tooth

blameless

adj
  • Free from blame; without fault; innocent 

  • Not meriting blame or censure; undeserving of reproof. 

clean as a hound's tooth

adj
  • Very clean; very innocent. 

How often have the words blameless and clean as a hound's tooth occurred in a corpus of books? (source: Google Ngram Viewer )