He was charged with murder, but got off on a plea of insanity.

他被指控犯了谋杀罪，但以精神错乱为由逃过惩罚。

《牛津词典》

Each time I visited the Sloans, I'd search for signs of insanity, misery or even regret in their super clean home, yet I never seemed to find any.

每次去拜访斯隆家，我都会在他们干净无比的家里寻找他们精神错乱、痛苦甚至后悔的迹象，但我似乎从来没有找到过。

youdao

He was found not guilty, by reason of insanity.

他以精神失常为理由获判无罪。

《牛津词典》

He did not want such a defense. The matter of insanity was dropped.

VOA: special.2009.07.02

Well, Plato thinks that the empirical world has something of that kind of insanity, something of that kind contradictoriness, built into it that we don't ordinarily notice.

柏拉图认为,现实的世界也是类似的疯狂,这其中有一种矛盾性,但我们身在其中一般不会注意到

耶鲁公开课 - 死亡课程节选

They asked the court to declare him innocent because of insanity.

VOA: special.2009.07.02

Analysts initially expected Mr Holmes to enter a plea of not guilty by reason of insanity.

BBC: Aurora shooting: Not guilty plea entered for James Holmes

Do you have some threshold constitutional right to make some kind of insanity defense?

NPR: Slate's Jurisprudence: Moussaoui's Insanity Defense

The definition of insanity is doing the same thing over and over, while expecting a different result.

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