material witness

基本解释

An FBI agent looks to track down a material witness who is involved in…
一名联邦调查局特工试图追查一位曾参与某绝密调查的关键证人。
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Testimony of a witness and material evidence are the existent forms of evidence.
诉讼中的证据与事实，是形式与内容的关系。
The prosecution's case collapsed when a material witness failed to appear in court.
一名重要的证人没有出庭，因此诉讼辩论无法进行。

And initially when he was arrested, government authorities designated him a material witness to terrorism.
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The driver was Ismail Elbarasse and detained on an outstanding material witness warrant issued in Chicago in connection with fundraising for Hamas.
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The plaintiff, Abdullah Al-Kidd, alleges that prosecutors never had any intention of calling him as a witness and submitted a false affidavit for the purpose of persuading a federal magistrate to issue a material witness warrant.
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