Honorable mentions:
source: from the Nuremberg prosecutor Ben Ferencz
that clip's from right before his death, but earlier in his life he said
"I watched it happen and did nothing. It was not my duty to stop it, even if I could have, and frankly, I was not inclined to try. There seemed to be no limit to human brutality in wartime. I headed back to Munich to write my reports." -Benjamin B. Ferencz