A subpoena is a court order to attend court, produce documents or both.
Although it is normally prepared and filed by the defence or prosecution in criminal proceedings, it is important to be aware that the failure to comply can amount to a breach of a court order, and have serious consequences.
There are three types of subpoenas (in NSW) (pronounced supeena):
- Subpoena for Production: A court order that requires a person to produce documents
- Subpoena to Give Evidence: A court order that requires a person to attend a hearing to give evidence
- Subpoena for Production and to Give Evidence: A court order that requires a person to produce documents and attend a hearing to give evidence. 
Failure to comply
Section 229 of the Criminal Procedures Act provides that the party who requested the subpoena may apply to the court for a warrant for the arrest of a person who fails to comply with a subpoena.
The court may issue an arrest warrant if satisfied that:
- The person named has not complied with the subpoena
- The requirements of the subpoena were complied with and no just or reasonable excuse has been offered for the failure to comply. 
Refusing to Give Evidence
Under section 231, a person who attends court in answer to a subpoena to give evidence and refuses to testify can be imprisoned for up to 7 days.
The court also has the power to bring common law charges for contempt of court, which is any act that has the tendency to interfere with or undermine the authority, performance or dignity of the courts or those who participate in their proceedings: Witham v Holloway (1995) 183 CLR 525 per McHugh J at 538-539.
Contempt in the face of the court is an act which has the tendency to interfere with or undermine the authority, performance or dignity of the courts or those who participate in their proceedings: Witham v Holloway (1995) 183 CLR 525 per McHugh J at 538-539.
Examples of contempt include:
- abusing and swearing at a magistrate: Prothonotary of the Supreme Court of NSW v Hall NSWSC 994
- filming witnesses with a view to intimidation: Prothonotary of the Supreme Court of NSW v Rakete(2011) 202 A Crim R 117
- prevaricating or refusing to answer questions: Keeley v Brooking(1979) 143 CLR 162
- refusing to take the oath or give evidence: Smith v R(1991) 25 NSWLR 1
- refusing to leave the court when directed: In the matter of Bauskis NSWSC 908
- disobeying court orders including subpoena:O’Shane v Channel Seven Sydney Pty Ltd  NSWSC 1358.