What is a 'subpoena' in the context of civil procedure?

A subpoena is a legal document issued by a court or an attorney that commands a person to appear in court as a witness or to produce certain documents or evidence relevant to a legal proceeding. This instrument is crucial in civil procedure as it enforces the attendance of witnesses or the submission of evidence that may be necessary for the resolution of a case. The legal weight of a subpoena means that failure to comply can lead to legal penalties, which underscores its role in ensuring that proceedings are conducted fairly and that all relevant information is available to the court.

In contrast, the other options describe different legal instruments or notifications. For instance, a document requesting witnesses to appear voluntarily does not have the binding authority of a subpoena; it lacks the enforceability that compels attendance. Similarly, a notice to inform a party of impending legal actions pertains to initiating legal processes but does not involve compelling action or testimony from individuals. Finally, a request for a judge’s instructions on a case relates to seeking clarity on procedural matters rather than enforcing the production of evidence or testimony pertinent to the case at hand.