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