kill by hanging vs neutralize

kill by hanging

verb
  • to kill someone by suspending them by the neck 

neutralize

verb
  • To kill. 

  • To make even, inactive or ineffective. 

  • To make (a territory, etc.) politically neutral. 

  • To make (an acidic or alkaline substance) chemically neutral. 

How often have the words kill by hanging and neutralize occurred in a corpus of books? (source: Google Ngram Viewer )