An Illinois Subpoena In a Civil Matter (For Testimony and-Or Documents) is a document that is issued by the court to compel a person to appear in court and provide testimony or documents relevant to a civil case. This subpoena is issued in the state of Illinois and is used in civil cases, not criminal cases. There are two types of Illinois Subpoena In a Civil Matter (For Testimony and-Or Documents): a Subpoena Ducks Cecum, which requires the recipient to produce documents, and a Subpoena Ad Testificandum, which requires the recipient to appear in court and provide testimony. The Illinois Subpoena In a Civil Matter (For Testimony and-Or Documents) must be served upon the recipient in person or by registered mail, and must include the name of the court, the case number, the name of the parties, and the date and time of the court appearance. The person served must either comply with the subpoena or file a motion to quash the subpoena. Failure to comply with a valid subpoena may result in a finding of contempt of court.