Subpoena

Writ to compel testimony or the yielding of evidence

A subpoena (also subpena, subpœna) or witness summons is a writ issued by a government agency, most often a court, to compel testimony by a witness or production of evidence under a penalty for failure. There are two common types of subpoenas: subpoena ad testificandum orders a person to testify before the ordering authority or face punishment. subpoena duces tecum orders a person or organization to bring physical evidence before the ordering authority or face punishment.

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