Under what circumstances can the fixed court date be changed?

For some reason, the court can't hear the criminal case according to the original court session, or in the course of the court session, it meets enough circumstances to continue the trial and decides to set another date for the trial. In criminal proceedings, if one of the following circumstances affects the court hearing, the trial may be postponed: ① It is necessary to notify new witnesses to appear in court, obtain new material evidence, re-evaluate or conduct an inquest. (2) Procurators find that public prosecution cases need supplementary investigation and make suggestions. (3) If the collegial panel considers that the evidence of the case is insufficient, or finds new facts, it needs to be returned to the people's procuratorate for supplementary investigation or self-investigation. (4) The trial cannot be conducted because the parties apply for withdrawal. In the trial practice, the trial can also be postponed under any of the following circumstances: ① The defendant refuses the defender to defend him in court and requests to entrust another defender. (2) The defendant or defender requests to prepare a defense because the people's procuratorate changes the scope of prosecution and proposes a new charge. (3) The defendant is unwell and it is indeed difficult to continue interrogation. (4) Members of the collegial panel, clerks, public prosecutors and defenders are unwell and cannot continue the trial. The postponement of the trial shall be decided by the court and announced publicly. In civil litigation, the trial of a case is temporarily suspended for reasons prescribed by law, and the trial is resumed after the reasons for suspension disappear, which is called litigation suspension.