Subpoena

The term subpoena is the historic name for a court order compelling a witness either to attend and give oral evidence (subpoena ad testificandum) or to produce documents to the court (subpoena duces tecum). In modern civil procedure in England and Wales, the term has been replaced by 'witness summons'. The Civil Procedure Rules define a witness summons as a document issued by the court requiring a witness to attend court to give evidence, or produce documents to the court, and provide that a separate witness summons is generally required for each witness.

HM Courts and Tribunals Service provides an official form, N20, for a party who wants to issue a witness summons requiring someone to give evidence at a hearing about a claim and/or to give requested documents. In criminal proceedings, the equivalent process is a witness summons issued under the Criminal Procedure (Attendance of Witnesses) Act 1965 (for the Crown Court) or section 97 of the Magistrates' Courts Act 1980 (for the magistrates' court), typically sought where a witness has declined to attend court voluntarily to give evidence for the prosecution. Failing to comply with a witness summons without a valid excuse can expose the witness to further court process, including a warrant for their attendance.