An Illinois Subpoena Ducks Cecum Before Grand Jury is a court order issued by a judge that requires a witness to appear before a grand jury and produce documents or other tangible evidence. The documents or other evidence must be related to the grand jury's investigation. The subpoena will typically include a list of the items that must be produced. There are two types of Illinois Subpoena Ducks Cecum Before Grand Jury: the Civil Subpoena Ducks Cecum and the Criminal Subpoena Ducks Cecum. The Civil Subpoena Ducks Cecum is issued when a party needs evidence for a civil case, such as a divorce or contract dispute. The Criminal Subpoena Ducks Cecum is issued when a witness must provide evidence related to a criminal matter, such as a drug investigation. Both types of subpoenas must be served on the witness by a law enforcement officer or other authorized individual. The witness must then appear in court with the requested documents or evidence. The witness may also be asked to testify before the grand jury.