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》

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In August, federal prosecutors and a judge accepted Albrett's plea of not guilty by reason of insanity.

八月，联邦检察官和法官因阿尔布若特精神错乱，接受了其无罪的抗辩。

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Last week, defense attorneys publicly acknowledged for the first time that they were considering an insanity plea.

NPR: Colo Shooting Suspect Was Hospitalized, Restrained

An insanity plea is at the intersection of law and psychology or psychiatry.

FORBES: Holmes Wants to Plead Insanity For Colorado Theater Shooting. What Does Insanity Mean?

But an insanity plea could make such a move harder, said David Beller, an attorney who is not connected to the case.

CNN: Judge enters not guilty plea for accused theater shooter