Political loyalty, military obedience are excellent things, but they neither require nor do they justify the commission of patently wicked acts. There comes a point where a man must refuse to answer to his leader if he is also to answer to his conscience.

Hartley Shawcross
Hartley Shawcross (1902-2003) English barrister, politician, diplomat
Opening remarks, Nuremberg War Crimes Tribunal (4 Dec 1945)
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Shawcross was Attorney General of the UK and Chief Prosecutor for the UK at the tribunal